Dispersible alcohol/cleaning wipes via topical or wet-end application of acrylamide or vinylamide/amine polymers

ABSTRACT

The present invention is directed to a wet wipe product. The wet wipe product comprises a fibrous substrate and a triggerable binder formulation. The triggerable binder formulation is capable of binding the fibers in the fibrous substrate. The triggerable binder formulation may include acrylamide polymers, vinylamide/amine polymers, and mixtures. The triggerable binder formulation is insoluble in a wetting composition comprising an insolubilizing agent but is dispersible in disposal water.

BACKGROUND OF THE INVENTION

For many years, the problem of disposability has plagued industries thatprovide disposable products such as diapers, wet wipes, adultincontinent garments and feminine care products. While much headway hasbeen made in addressing this problem, one of the weak links has been theinability to create an economical coherent fibrous web which willreadily dissolve or disintegrate in water but still have sufficientin-use tensile strength.

Binder compositions have been developed which can be more dispersibleand are more environmentally responsible than past binder compositions.One class of binder compositions includes polymeric materials havinginverse solubility in water. These binder compositions are insoluble inwarm water, but are soluble in cold water, such as found in a toilet. Itis well known that a number of polymers exhibit cloud points or inversesolubility properties in aqueous media. These polymers include: (1)evaporation retarders; (2) temperature sensitive compositions, which areuseful as temperature indicators due to a sharp color change associatedwith a corresponding temperature change; (3) heat sensitive materialsthat are opaque at a specific temperature and become transparent whencooled to below the specific temperature; (4) wound dressings with goodabsorbing characteristics and easy removal; and, (5) materials influshable personal care products.

Other binders include a class of binders Which are ion-sensitive. Insome cases, terpolymers are used as binders for flushable nonwoven webs.The acrylic acid-based terpolymers, which comprise partially neutralizedacrylic acid, butyl acrylate and 2-ethylhexyl acrylate, may be used asbinders for use in flushable nonwoven webs in some parts of the world.However, because of the presence of a small amount of sodium acrylate inthe partially neutralized terpolymer, such binders fail to disperse inwater containing more than about 15 ppm Ca²⁺ and/or Mg²⁺. When placed inwater containing more than about 15 ppm Ca²⁺ and/or Mg²⁺ ions, nonwovenwebs using the above-described binders maintain a tensile strengthgreater than 30 g/in, which negatively affects the “dispersibility” ofthe nonwoven web. The proposed mechanism for the failure is that eachcalcium ion binds with two carboxylate groups either intramolecularly orintermolecularly. Intramolecular association causes the terpolymer chainto coil up, which eventually leads to polymer precipitation.Intermolecular association yields crosslinking. Whether intramolecularor intermolecular associations are taking place, the terpolymer is notsoluble in water containing more than about 15 ppm Ca²⁺ and/or Mg²⁺. Dueto the strong interaction between calcium ions and the carboxylategroups of the terpolymer, dissociation of the complex is highly unlikelybecause this association is irreversible. Therefore, the terpolymer thathas been exposed to a high Ca²⁺ and/or Mg²⁺ concentration solution willnot disperse in water even if the calcium concentration decreases. Thislimits the application of the terpolymer as a flushable binder materialbecause most areas across the U.S. have hard water, which contains morethan 15 ppm Ca²⁺ and/or Mg²⁺.

Other binders, while being in contact with an organic solvent, usuallyas a cleaning agent or a preservative, still require the presence ofions, such as monovalent or divalent metal ions, to establish sufficientstability during use and dispersibility at disposal. As discussed above,the issue of hard water may again apply to such binders.

In some dispersible cleaning or personal care products, such as awater-disintegratable cleansing sheet; i.e., wet wipe, comprisingwater-dispersible fibers treated with a water-soluble binder having acarboxyl group. The cleansing sheet is treated with a cleansing agentcontaining 5%-95% of a water-compatible organic solvent and 95%-5%water. The organic solvent is typically propylene glycol. The cleansingsheet retains wet strength and does not disperse in the organicsolvent-based cleansing agent, but disperses in water. The cleansingsheets must have higher concentrations of organic solvents as thesesolvents ensure the in-use wet strength for the cleansing sheets.Without the solvents, the cleansing sheets would have little in-use wetstrength and would not be effective as a wet wipe. However, the use ofsuch high amounts of organic solvent results in a greasy after-feel whenthe cleansing sheet is used, and these organic solvents may causediscomfort and irritation to skin in higher amounts.

There exists a need for dispersible cleaning or personal care productspossessing softness, flexibility, three dimensionality, and resiliency;wicking and structural integrity in the presence of aqueous or bodilyfluids; and, true fiber dispersion after toilet flushing so that thecleaning or personal care product does not become entangled atobstructions, such as with tree roots or at bends, in sewer pipes.Moreover, there is a need in the art for flushable cleaning or personalcare products having water-dispersibility in all areas of the world,including soft and hard water areas. Furthermore, there is a need forwater-dispersible binders that do not reduce wettability of the cleaningor personal care product with which they are used and are sprayable forrelatively easy and uniform application to and penetration into thecleaning or personal care products. Finally, there is a need forwater-dispersible, flushable wet wipes that are stable during storageand retain a desired level of wet strength during use when wetted withthe appropriate cleaning, disinfection, or sanitizing wettingcomposition. Such a cleaning or personal care product is needed at areasonable cost without compromising product safety and environmentalconcerns, something that past products have failed to do.

SUMMARY OF THE INVENTION

The present invention is directed to triggerable binder formulations ofacrylamide and vinylamide/amine polymers and polymer formulations, whichhave been developed to address the above-described problems. As usedherein, the term “polymer” is understood to include polymers,copolymers, terpolymers, and higher order polymers. The triggerablebinder formulations of the present invention may provide strength in thedry state, but more importantly, may help maintain a desired level ofstrength of the fibrous substrate in the wet state by solventtriggerability. A controlled concentration of an insolubilizing agent,such as a lower level alcohol, glycol, ketone, or mixtures thereof, inthe wetting composition insolubilizes the triggerable binder formulationand allows it to function as an adhesive for the fibers to form orfurther enhance a fibrous substrate. When the wet wipe is discarded intothe wastewater stream, the insolubilizing agent concentration isdiluted, the triggerable binder formulation becomes soluble, and thestrength of the fibrous substrate drops below a critical level. Thetriggerable binder formulations of the present invention have a “triggerproperty,” such that the triggerable binder formulations are insolublein a wetting composition comprising an insolublizing agent of aparticular type and concentration, such as alcohol, glycol, ketone, ormixtures thereof at concentrations above about 50% by weight, but aresoluble when diluted with water, including hard water having 500 ppm(parts per million) or greater of calcium and magnesium ions. Thisallows the fibrous substrate to break apart into small pieces and,ultimately, disperse.

Unlike some ion-sensitive polymer formulations, which losedispersibility in hard water because of ion cross-linking by calciumions, the triggerable binder formulations of acrylamide andvinylamide/amine polymers and polymer formulations of the presentinvention are insensitive to calcium and/or magnesium ions atconcentrations of a few hundred ppm and are insensitive to pHvariations. Consequently, flushable cleaning or personal care productscontaining the triggerable binder formulations of the present inventionmaintain dispersibility of the fibrous substrates in hard water or softwater.

The polymers and polymer formulations of the present invention areuseful as triggerable binder formulations and structural components forair-laid and wet-laid fibrous substrates, such as nonwoven fabrics, forapplications, such as cleaning, hard surface cleaning, disinfecting,sanitizing, and personal care products. The polymers and polymerformulations of the present invention are particularly useful astriggerable binder formulations for flushable cleaning and personal careproducts, particularly wet wipes for personal use, such as cleaning ortreating skin, make-up removal, nail polish removal, medical care, andalso wipes for use in hard surface cleaning, automotive care, includingwipes comprising cleaning agents, disinfectants, and the like. Theflushable cleaning or personal care products maintain integrity or wetstrength during storage and use, and break apart or disperse afterdisposal in the toilet when the alcohol concentration falls below acritical level. Suitable fibrous substrates for treatment with thetriggerable binder formulations of the present invention include, butare not limited to tissue, such as creped or uncreped tissue, coformproducts, hydroentangled webs, airlaid mats, fluff pulp, nonwoven webs,and composites thereof. Methods for producing uncreped tissues andmolded three-dimensional tissue webs of use in the present invention maybe found in commonly owned U.S. Pat. No. 6,436,234, issued to Chen etal. on Aug. 20, 2002; U.S. Pat. No. 5,429,686, issued to Chiu et al. onJul. 4, 1995; U.S. Pat. No. 5,399,412, issued to S. J. Sudall et al. onMar. 21, 1995; U.S. Pat. No. 5,672,248, issued to Wendt et al. on Sep.30, 1997; and U.S. Pat. No. 5,607,551, issued to Farrington et al. onMar. 4, 1997; the disclosures of which are incorporated by reference tothe extent they are non-contradictory herewith. The molded tissuestructures of the above patents may be especially helpful in providinggood cleaning in a wet wipe. Good cleaning may also be promoted byproviding a degree of texture in the fibrous substrates as well byembossing, molding, wetting and through-air drying on a textured fabric,and the like. The acrylamide and vinylamide/amine polymers and polymerformulations of the present invention are particularly useful astriggerable binder formulations for fibrous substrates because theacrylamide and vinylamide/amine polymers and polymer formulations aresubstantive to the fibers.

Air-laid material may be formed by metering an airflow containing thefibers and other optional materials, in substantially dry condition,onto a typically horizontally moving wire forming screen. Suitablesystems and apparatus for air-laying mixtures of fibers andthermoplastic material are disclosed in, for example, U.S. Pat. No.4,157,724, issued to Persson on Jun. 12, 1979 and reissued on Dec. 25,1984 as Re. U.S. Pat. No. 31,775; U.S. Pat. No. 4,278,113, issued toPersson on Jul. 14, 1981; U.S. Pat. No. 4,264,289, issued to Day on Apr.28, 1981; U.S. Pat. No. 4,352,649, issued to Jacobsen et al. on Oct. 5,1982; U.S. Pat. No. 4,353,687, issued to Hosler, et al. on Oct. 12,1982; U.S. Pat. No. 4,494,278, issued to Kroyer, et al. on Jan. 22,1985; U.S. Pat. No. 4,627,806, issued to Johnson 4 on Dec. 9; 1986; U.S.Pat. No. 4,650,409, issued to Nistri, et al. on Mar. 17, 1987; and, U.S.Pat. No. 4,724,980, issued to Farley on Feb. 16, 1988; and, U.S. Pat.No. 4,640,810, issued to Laursen et al. on Feb. 3, 1987, the disclosuresof which are incorporated by reference to the extent that they arenon-contradictory herewith.

The present invention also discloses how to make water-dispersiblefibrous substrates, including wet wipes, which are stable in wettingcompositions having an insolubilizing content, such as alcohol, glycol,ketone, or mixtures thereof, using the above-described unique polymersand polymer formulations as triggerable binder compositions. Theresultant treated fibrous substrates are flushable and water-dispersibledue to the tailored sensitivity for insolubilizing agents, which can betriggered regardless of the hardness of water found in toiletsthroughout the United States and the world.

The present invention further discloses a suitable wetting compositionfor wet wipes. Wet wipes employing the polymers and polymer formulationsas triggerable binder formulations of the present invention are stableduring storage and retain a desired level of in-use tensile strengthduring use and are wetted with a wetting composition or cleaning agentcomprising an insolubilizing agent, such as a lower level alcohol,glycol, ketone, or mixtures thereof.

These and other objects, features and advantages of the presentinvention will become apparent after a review of the following detaileddescription of the disclosed embodiments and the appended claims.

DETAILED DESCRIPTION OF THE DISCLOSED EMBODIMENTS

The present invention is practiced using triggerable binder formulationscomprising acrylamide and vinylamide/amine polymers or polymerformulations. The triggerable binder formulations are an insolubilizingagent-sensitive acrylamide and vinylamide/amine polymer and polymerformulations. In order to be an effective insolubilizing agent-sensitiveor triggerable polymer or polymer formulation for use in flushable orwater-dispersible cleaning or personal care products, the triggerablebinder formulations may be: (1) functional, i.e., maintain wet strengthof the fibrous substrate under controlled conditions and dissolve ordisperse in a reasonable period of time in soft or hard water, such asfound in toilets and sinks around the world, thereby allowing thefibrous substrate dissolve or disperse; (2) safe (not toxic); and, (3)relatively economical. In addition to the foregoing factors, theinsolubilizing agent-sensitive or triggerable binder formulations whenused as a binder material for a fibrous substrate, such as a nonwovenfabric for use in a pre-moistened wipe or wet wipe (hereinafter referredto as wet wipe), may be: (4) processable on a commercial basis; i.e.,may be applied relatively quickly on a large scale basis, such as byspraying, coating, printing, and the like; (5) provide acceptable levelsof sheet or fibrous substrate wettability; (6) provide acceptable levelsof sheet or fibrous substrate stiffness; and, (7) reduced tackiness ofthe fibrous substrate or the product that the fibrous substrate isincorporated into. The wetting composition with which the wet wipes ofthe present invention are treated may provide some of the foregoingadvantages, and, in addition, may provide: (8) improved tactileproperties; and, (9) cleaning, disinfecting, sanitizing properties. Theinsolubilizing agent-sensitive or triggerable binder formulations of thepresent invention and products made therewith, especially wet wipescomprising particular wetting compositions set forth below, may meetmany or all of the above criteria. Of course, it is not necessary forall of the advantages of the embodiments of the present invention to bemet to fall within the scope of the present invention.

Alcohol Triggerable Acrylamide and Vinylamide/amine Polymers and PolymerFormulations

The insolubilizing agent-sensitive or triggerable binder formulations ofthe present invention comprise acrylamide and vinylamide/amine polymersand polymer formulations. The insolubilizing agent-sensitive ortriggerable binder polymers may function as adhesives for tissue,airlaid pulp, wetlaid pulp, and other fibrous substrates and providesufficient in-use tensile strength (typically about 300 g/in. orgreater; about 500 g/in. or greater; or, about 1,000 g/in. or greater)when wetted with a wetting composition. The fibrous substrates may alsobe dispersible in tap water (including hard water up to 500 ppm orgreater as metal ion), typically losing most of their in-use tensilestrength between about 30 to about 75 g/in. in about 24 hours or less.Such insolublizing agent-sensitive or triggerable binder formulationsgenerally have the following structures:

The R₁ moiety may be hydrogen or methyl.

The R₁ and R₂ moieties may be independently hydrogen, methyl, ormixtures thereof. The Z moiety may be —O—, —COO—, —CONH—, —NHCO—, —NH2,—NHR, and —NR₂. The R₃ moiety may be hydrogen, or any C₁ or higher alkylgroup or aryl group, including methyl, ethyl, n-propyl, isopropyl,n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, ethylhexyl, and the like.

The R₁ and R₂ moieties may be independently hydrogen, methyl, ormixtures thereof. The R₃ moiety may be hydrogen, or any C₁ or higheralkyl group or aryl group, including methyl, ethyl, n-propyl, isopropyl,n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, ethylhexyl, and the like.

The R₁ moiety may be hydrogen or methyl. The R₃ moiety may be hydrogen,or any C₁ or higher alkyl group or aryl group, including methyl, ethyl,n-propyl, isopropyl, n-butyl, sec-butyl, tert-butyl, pentyl, hexyl,ethylhexyl, and the like.

The R₁ and R₂ moieties may be independently hydrogen, methyl, ormixtures thereof. The Z moiety may be —O—, —COO—, —CONH—, —NHCO—, —NH2,—NHR, and —NR₂. The R₃ moiety may be hydrogen, or any C₁ or higher alkylgroup or aryl group, including methyl, ethyl, n-propyl, isopropyl,n-butyl, sec-butyl, tert-butyl, pentyl, hexyl, ethylhexyl, and the like.

The R₁ moieties may be independently hydrogen, methyl, or mixturesthereof.Polyacrylamide Polymers and Polymer Formulations

Polyacrylamide polymers and polymer formulations may be anionic,neutral, amphoteric, or positive in charge. Polymethacrylamide and otheranalogs may also be utilized. The presence of additional hydrophilic orcharged groups may enhance solubility, dispersibility, and otherproperties of the polymers and polymer formulations.

Examples of anionic or acidic monomers that may copolymerized into thebackbone of the polymers and polymer formulations may include acrylicacid, methacrylic acid and their salts, 2-acrylamido-2-methyl-1propanesulfonic acid (AMPS) and its salts, vinyl sulfonic acid and theirsalts, other sulfonate monomers such as potassium (3-sulfopropyl)acrylate, sodium styrene sulfonate, and phosphonate/phosphonic acidsmonomers. Useful neutral monomers include ones such as N-isopropylacrylamide and other acrylamide derivatives, 2-hydroxylethylmethacrylate, vinyl pyrrolidone, methylvinyl ether, and polyethyleneglycol (PEG) acrylate or methacrylates. Useful amphoteric orzwitterionic monomers includeN,N-Dimethyl-N-(2-methacryloyloxyethyl)-N-(3-sulfopropyl) ammoniumbetaine, N,N-dimethyl-N-(2-methacrylamidopropyl)-N-(3-sulfopropyl)ammonium betaine, 1-(3-Sulfopropyl)-2-vinylpyridinium betaine,N-(3-carboxypropyl)-N-methacrylamido-ethyl-N,N-dimethyl ammoniumbetaine, and 4-vinylpiperidinium ethanecarboxy betaine. Useful cationicmonomers include [2-(acryloxy)ethyl] trimethyl ammonium chloride(ADAMQUAT), [2-(methacryloxy)ethyl] trimethyl ammonium chloride(MADQUAT), (3-acrylamidopropyl) trimethyl ammonium chloride,N,N-diallyldimethyl ammonium chloride, [2-(acryloxy)ethyl]dimethylbenzyl ammonium chloride, (2-(methacryloxy)ethyl) dimethylbenzylammonium chloride, [2-(acryloxy)ethyl] dimethyl ammonium chloride, and[2-(methacryloxy)ethyl] dimethyl ammonium chloride. Precursor monomerssuch as vinylpyridine, dimethylaminoethyl acrylate, anddimethylaminoethyl methacrylate, which may be polymerized andquaternized through post-polymerization reactions may be used in thepresent invention. Monomers or quaternization reagents which providedifferent counter-ions such as bromide, iodide, or methyl sulfate arefurther alternatives applicable to the present invention. In someembodiments of the present invention, certain water-insoluble monomersmay be used to lower the Tg of the polyacrylamide polymers or polymerformulations or to provide other useful properties, wherein theinsolubility in the presence of an insolubilizing agent is notcompromised or solubility in water is not compromised. Suchwater-insoluble monomers may include lower level acrylates, such asmethyl, ethyl or butyl acrylates, substituted acrylamides, alkyl vinylethers, or other vinyl monomers.

Preparation of Polyvinylamide/amines Polymers and Polymer Formulations

Polyvinylamide/amine polymers or polymer formulations are typicallyproduced by free radical polymerization of N-vinylamide monomers withdegree of cationicity controlled by post-polymerization hydrolysis andpH. Such N-vinylamide monomers may include N-vinylformamide,N-vinylacetamide, and other N-vinyl alkylamides. Co-polymerizationproducts of the N-vinylamide monomers with other monomers such as thosedescribed above may be useful in the present invention. One embodimentof the present invention may be the co-polymerization product of theN-vinylamide monomer with a vinyl ester monomer, such as vinyl acetate.Hydrolysis may yield co-polymers of vinylamine/amide monomers with vinylalcohol monomers. The hydrolyzed polymer or polymer formulation may behighly reactive with a host of functional chemistries, resulting in thepotential for unique combinations of properties in a water solublepolymer. Examples of said functional chemistries may include cyclicesters, epoxides, isocyanantes, carboxylates, organic (i.e. alkyl)halides, aldehydes, etc., wherein the insolubility in the presence of aninsolubilizing agent is not compromised or solubility in water is notcompromised.

Cyclic amide polymers or polymer formulations, such aspolyvinylpyrrolidone and polyvinylcaprolactam, may also be useful in thepresent invention.

The acrylamide and vinylamide/amine polymers and polymer formulations ofthe triggerable binder formulations of the present invention may have anaverage molecular weight that varies depending on the ultimate use ofthe triggerable binder formulation. The triggerable binder formulationof the present invention may have a weight average molecular weightranging from about 10,000 to about 1,000,000 grams per mol. Morespecifically, the triggerable binder formulations of the presentinvention may have a weight average molecular weight ranging from about25,000 to about 500,000 grams per mol., or, more specifically still,from about 200,000 to about 400,000 grams per mol.

In one embodiment of the present invention, the above-describedtriggerable binder formulations may be used as binder materials forflushable and/or non-flushable cleaning or personal care products. Inorder to be effective as a binder material in flushable cleaning orpersonal care products throughout the United States, the triggerablebinder formulations of the present invention may remain stable andmaintain their integrity (in-use tensile strength) while dry or inrelatively high concentrations of an insolubilizing agent, such as lowerlevel alcohols, lower level glycols, lower level ketones, and mixturesthereof, but become soluble in water when the concentration of theinsolubilizing agent drops below about 50%. The triggerable binderformulations of the present invention may be insoluble in a solutioncontaining at least about 50 weight percent of an insolubilizing agent,such as a lower level alcohol, lower level glycol, lower level ketone,and mixtures thereof. More specifically, the triggerable binderformulations of the present invention may be insoluble in a solutioncontaining from about 50% to about 100% by weight of an insolubilizingagent, such as a lower level alcohol, a lower level glycol, a lowerlevel ketone, and mixtures thereof. Even more specifically, thetriggerable binder formulations of the present invention may beinsoluble in a solution containing from about 65% to about 90% by weightof an insolubilizing agent, such as lower level alcohol, lower levelglycol, ketone, and mixtures thereof. More specifically, the triggerablebinder formulations of the present invention may be insoluble in asolution containing from about 70% to about 90% by weight of aninsolubilizing agent, such as lower level alcohol, lower level glycol,lower level ketone, and mixtures thereof.

Suitable lower level alcohols, lower level glycols, lower level ketones,and mixtures thereof that may be utilized as insolubilizing agents, mayinclude, but are not limited to: methyl alcohol; ethyl alcohol; n-propylalcohol; isopropyl alcohol; n-butyl alcohol; sec-butyl alcohol;tert-butyl alcohol; ethylene glycol; 1,2 propandiol (propylene glycol);1,3 propane diol; acetone; methylethyl ketone; and, mixtures thereof.

In some embodiments of the present invention where the objective of thecleaning or personal care product is to provide disinfecting,sanitizing, or sterilizing properties, it may be undesirable to use aneat solvent wetting solution. It is known that the inclusion of watermay enhance the disinfecting, sanitizing, or sterilizing properties ofthe wetting solution. Alcohols disinfect, sanitize, or sterilizeprimarily through denaturation (precipitation) of proteins that make upthe cell wall of bacteria and other microorganisms. This denaturingeffect may be less effective in the absence of water.

Additional insolubilizing agents useful in the present invention mayinclude water-immiscible solvents. Hydrocarbons, such as C₆ and higheralkanes, including hexanes and octanes, toluenes, xylene, methylenechloride, and chloroform may be useful as insolublizing agents inwetting compositions.

Triggerable Binder Formulations and Fibrous Substrates Containing theSame

The triggerable binder formulations of acrylamide and vinylamide/aminepolymers and polymer formulations of the present invention may be usedas binders. The triggerable binder formulations of the present inventionmay be applied to any fibrous substrate. The triggerable binderformulations are particularly suitable for use in water-dispersiblecleaning or personal care products. Suitable fibrous substrates include,but are not limited to, nonwoven and woven fabrics. In many embodiments,particularly cleaning or personal care products, fibrous substrates maybe nonwoven fabrics. As used herein, the term “nonwoven fabric” refersto a fibrous substrate that has a structure of individual fibers orfilaments randomly arranged in a mat-like fashion (including papers).Nonwoven fabrics may be made from a variety of processes including, butnot limited to, air-laid processes, wet-laid processes, hydroentanglingprocesses, staple fiber carding and bonding, solution spinning, and anyother method known to one skilled in the art.

The triggerable binder formulation may be applied to the fibroussubstrate by any known process of application. Suitable processes forapplying the triggerable binder formulation include, but are not limitedto, printing, spraying, electrostatic spraying, coating, flooded nips,metered press rolls, impregnating or by any other technique. The amountof the triggerable binder formulation may be metered and distributeduniformly within the fibrous substrate or may be non-uniformlydistributed within the fibrous substrate. The triggerable binderformulation may be distributed throughout the entire fibrous substrateor it may be distributed within a multiplicity of small closely spacedareas. The triggerable binder formulation may be applied to the fibersprior to incorporation of the fibers into a fibrous substrate.

The solution of the triggerable binder formulation may contain up toabout 50 percent by weight of triggerable binder formulation solids.More specifically, the solution of the triggerable binder formulationmay contain from about 2 to about 20 percent by weight of triggerablebinder formulation solids, more specifically about 5 to about 10 percentby weight of triggerable binder formulation solids. Plasticizers,perfumes, coloring agents, antifoams, bactericides, preservatives,surface active agents, thickening agents, fillers, opacifiers,tackifiers, detackifiers, co-binder polymers, and similar additives maybe incorporated into the solution of the triggerable binder formulation,if so desired.

Once the triggerable binder formulation is applied to the fibroussubstrate, the fibrous substrate may be dried by any conventional means.Once dry, the coherent fibrous substrate exhibits improved in-usetensile strength when compared to the in-use tensile strength of theuntreated wet-laid or air-laid fibrous substrates, and yet has theability to rapidly “fall apart”, or disintegrate when placed in soft orhard water having a divalent ion concentration of about 500 ppm orgreater of Ca²⁺ and/or Mg²⁺ and agitated. For example, the dry tensilestrength of the triggerable binder formulation treated fibrous substratemay be increased by at least about 25 percent as compared to the drytensile strength of the untreated fibrous substrate. More particularly,the dry tensile strength of the triggerable binder formulation treatedfibrous substrate may be increase by at least about 100 percent ascompared to the dry tensile strength of the untreated fibrous substrate.Even more particularly, the dry tensile strength of the fibroussubstrate treated with the triggerable binder formulation may beincreased by at least about 500 percent as compared to the dry tensilestrength of the untreated fibrous substrate.

One feature of the present invention is that the improvement in thein-use tensile strength is effected where the amount of triggerablebinder formulation present, “add-on”, in the resultant fibrous substratemay represent only a small portion by weight of the entire fibroussubstrate. The add-on level of the triggerable binder formulation maydepend upon the in-use tensile strength is that is desired in thefibrous substrate and the product into which the fibrous substrate isincorporated. Typically, dense, low caliper fibrous substrates mayrequire a lower add-on level of the triggerable binder formulation toobtain targeted properties while lofty, higher caliper fibroussubstrates may require a higher add-on level of the triggerable binderformulation to obtain targeted properties. In addition, wet-laid fibroussubstrates may require a lower add-on level of the triggerable binderformulation in the presence of an inherent dry strength resulting fromfiber-fiber hydrogen bonding. Air-laid fibrous substrates may require ahigher add-on level of the triggerable binder formulation because suchfibrous substrates typically lack an inherent dry strength becausehydrogen bonding is less likely to be present within the fibroussubstrate.

The amount of “add-on” may vary for a particular application; however,the optimum amount of “add-on” results in a fibrous substrate which hasintegrity (desired in-use tensile strength) while in use and alsoquickly disperses, referred to herein as disposal strength, (typicallyabout 75 g/in. or less; about 50 g/in. or less; or, about 20 g/in. orless) when soaked in water. Typically a lower add-on level is requiredfor wet-end application than for a topical application. For example, thetopical add-on level of the triggerable binder formulations may rangefrom about 0.5% to about 25%, by weight, of the total dry fiber weightof the fibrous substrate. More particularly, the topical add-on level ofthe triggerable binder formulation may range from about 2% to about 15%,by weight, of the total dry fiber weight of the fibrous substrate. Evenmore particularly, the topical add-on level of the triggerable binderformulations may be from about 5% to about 12% by weight of the totaldry fiber weight, of the fibrous substrate. For wet-end application, thewet-end add-on level of the triggerable binder formulations may rangefrom about 0.1% to about 2%, by weight, of the total dry fiber weight ofthe fibrous substrate. More particularly, the wet-end add-on level ofthe triggerable binder formulation may range from about 0.3% to about1%, by weight, of the total dry fiber weight of the fibrous substrate.Even more particularly, the wet-end add-on level of the triggerablebinder formulations may be from about 0.5% to about 1% by weight of thetotal dry fiber weight of the fibrous substrate.

The treated fibrous substrates of the present invention may have goodin-use tensile strength, as well as, triggerability based on thepresence of an insolubilizing agent. The fibrous substrates treated withthe triggerable binder formulation of the present invention may beabrasion resistant and retain significant tensile strength in aqueouswetting compositions containing the specific amount and type of theinsolubilizing agent, such as lower level alcohols, glycols, ketones,and mixtures thereof, disclosed herein.

The fibers forming the fibrous substrates may be made from a variety ofmaterials including natural fibers, synthetic fibers, and combinationsthereof. The choice of fibers depends upon, for example, the intendedend use of the finished fibrous substrate, such as a nonwoven fabric,and fiber cost. For instance, the fibrous substrates may include, butare not limited to, natural fibers such as cotton, linen, jute, hemp,wool, wood pulp, etc. Similarly, regenerated cellulosic fibers, such asviscose rayon and cuprammonium rayon, modified cellulosic fibers, suchas cellulose acetate, or synthetic fibers, such as those derived frompolypropylenes, polyethylenes, polyolefins, polyesters, polyamides,polyacrylics, etc., alone or in combination with one another, maylikewise be used. Blends of one or more of the above fibers may also beused, if so desired. Among the wood pulp fibers, any known papermakingpulp fibers may be used, including softwood and hardwood pulp fibers.Fibers, for example, may be chemically pulped or mechanically pulped,bleached or unbleached, virgin or recycled, high yield or low yield, andthe like. Mercerized, chemically stiffened or crosslinked fibers mayalso be used.

Synthetic cellulose fiber types include rayon in all its varieties andother fibers derived from viscose or chemically modified cellulose,including regenerated cellulose and solvent-spun cellulose, such asLyocell. C hemically treated natural cellulosic fibers may be used, suchas mercerized pulps, chemically stiffened or crosslinked fibers, orsulfonated fibers. Recycled fibers, as well as virgin fibers, may beused. Cellulose produced by microbes and other cellulosic derivativesmay be used. As used herein, the term “cellulosic” is meant to includeany material having cellulose as a major constituent, and, specifically,comprising at least 50 percent by weight cellulose or a cellulosederivative. Thus, the term includes cotton, typical wood pulps,non-woody cellulosic fibers, cellulose acetate, cellulose triacetate,rayon, thermomechanical wood pulp, chemical wood pulp, debonded chemicalwood pulp, milkweed, and bacterial cellulose.

The triggerable binder formulation of the present invention may also beapplied to other fibers or particles. Other fibers that may be treatedwith the triggerable binder formulation of the present invention mayinclude fibers such as those made fibers made from carboxymethylcellulose, chitin, and chitosan. The triggerable binder formulation ofthe present invention may also be applied to particles, such as sodiumpolyacrylate superabsorbent particles. Superabsorbent particles arefrequently incorporated on or into fibrous substrates used for cleaningor personal care products, especially nonwoven fabrics.

The fiber length is important in producing the fibrous substrates, suchas nonwoven fabrics, of the present invention. The minimum length of thefibers depends on the method selected for forming the fibrous substrate.For example, where the fibrous substrate is formed by carding, thelength of the fiber should usually be at least about 42 mm in order toinsure uniformity.

Where the fibrous substrate is formed by air-laid or wet-laid processes,the fiber length may desirably be about 0.2 to about 6 mm. Althoughfibers having a length of greater than 50 mm may be used, it has beendetermined that when a substantial quantity of fibers having a lengthgreater than about 15 mm is placed in a flushable fabric, though thefibers will disperse and separate in water, their length tends to form“ropes” of fibers, which are undesirable when flushing in home toilets.Therefore, for these products, it is desired that the fiber length beabout 15 mm or less so that the fibers will not have a tendency to“rope” when they are flushed through a toilet. Although fibers ofvarious lengths are applicable in the present invention, desirablyfibers are of a length less than about 15 mm so that the fibers disperseeasily from one another when in contact with water. The fibers,particularly synthetic fibers, may also be crimped.

The fibrous substrates, such as woven and nonwoven fabrics, may beformed from a single layer or multiple layers. In the case of multiplelayers, the layers are generally positioned in a juxtaposed orsurface-to-surface relationship and all or a portion of the layers maybe bound to adjacent layers. The fibrous substrates may also be formedfrom a plurality of separate webs wherein the separate webs may beformed from single or multiple layers. In embodiments of the presentinvention where the fibrous substrate includes multiple layers, theentire thickness of the fibrous substrate may be subjected to anapplication of the triggerable binder formulation or each individuallayer may be separately subjected to an application of the triggerablebinder formulation and then combined with other layers in a juxtaposedrelationship to form the finished fibrous substrate, such as woven ornonwoven fabrics.

In one embodiment of the present invention, the fibrous substrates maybe incorporated into cleaning products, such as wet wipes, cleaningwipes for cleansing hard surfaces, and the like. These products maycomprise one or more layers of a fluid-pervious element, such as fibroustissue, gauze, plastic netting, etc.

The triggerable binder formulations of the present invention may beuseful for binding fibers of air-laid or wet-laid fibrous substrates,such as nonwoven fabrics. The basis weights for air-laid or wet-laidfibrous substrates may range from about 10 grams per square meter(“gsm”) to about 200 gsm. More specifically, the basis weights for thefibrous substrates may range from about 20 gsm to about 70 gsm and morespecifically, from about 30 gsm to about 70 gsm. The basis weight,caliper, and other properties may be chosen to deliver desiredattributes such as bulk, stretch, resiliency, toughness, and the like.The air-laid fibrous substrates may be especially useful for a wet wipe.The basis weights for such air-laid fibrous substrates may range fromabout 20 gsm to about 200 gsm with staple fibers having a denier ofabout 0.5 to about 10 and a length of about 6 to about 15 millimeters.

The fibrous substrates may also be incorporated into such body fluidabsorbing products as pads, surgical dressings, tissues and the like.The triggerable binder formulation is such that it will not dissolvewhen contacted by body fluids. The fibrous substrate retains itsstructure, softness and exhibits a toughness satisfactory for practicaluse. However, when the fibrous substrate is brought into contact withwater having a concentration of an insolubilizing agent, such as a lowerlevel alcohol, lower level glycol, lower level ketone, or mixturesthereof, up to about 300 ppm or less, the triggerable binder formulationdisperses. The fibrous substrate is then easily broken and dispersed ordissolved in the water.

In one embodiment of the present invention, the in-use tensile strengthof a fibrous substrate may be enhanced by forming the fibrous substratewith a binder material comprising the triggerable binder formulation ofthe present invention and subsequently applying an insolubilizing agent,such as a lower level alcohol, glycol, ketone, or mixtures thereof, tothe fibrous substrate. The insolubilizing agent may be applied to thefibrous substrate by any method known to those of ordinary skill in theart including spraying a solution onto the fibrous substrate. The amountof the insolubilizing agent may vary depending on a particularapplication. However, the amount of the insolubilizing agent may beapplied to the fibrous substrate may be from about 50 weight percent toabout 700 weight percent of the insolubilizing agent based on the totalweight of the fibrous substrate. The insolubilizing agent-containingfibrous substrates of the present invention may be used in a variety offibrous substrates applications including, but not limited to, wipeproducts, such as wet wipes, cleaning wipes for hard surfaces, and thelike.

Those skilled in the art will readily understand that the triggerablebinder formulations and fibrous substrates of the present invention maybe advantageously employed in the preparation of a wide variety ofproducts, including but not limited to, cleaning or personal careproducts designed to be contacted with body fluids. Such cleaning orpersonal care products may only comprise a single layer of the fibroussubstrate, or may comprise a combination of elements, as describedabove. Although the triggerable binder formulations and fibroussubstrates of the present invention are particularly suited for cleaningor personal care products, the triggerable binder formulations andfibrous substrates may be advantageously employed in a wide variety ofconsumer products.

The triggerable binder formulations of the present invention may beactivated as binders without the need for elevated temperature. Whiledrying or water removal may be useful in achieving a good distributionof the triggerable binder formulation in a fibrous substrate, elevatedtemperature, per se, is not essential because the triggerable binderformulation does not require crosslinking or other chemical reactionswith high activation energy to serve as a within the fibrous substrate.Rather, the interaction with a soluble insolubilizing agent, typically alower level alcohol, glycol, ketone, or mixtures thereof, is sufficientto cause the triggerable binder formulation to become insoluble; i.e.,activated by interaction between the insolubilizing agent and thetriggerable binder formulation. Thus, a drying step may be avoided, ifdesired, or replaced with low-temperature water removal operations suchas room-temperature drying or freeze drying. Elevated temperature isgenerally helpful for drying, but the drying may be done at temperaturesbelow what is normally needed to drive crosslinking reactions. Thus, thepeak temperature to which the fibrous substrate is exposed or to whichthe fibrous substrate is brought may be below any of the following: 200°C., 180° C., 160° C., 140° C., 120° C., 110° C., 105° C., 100° C., 90°C., 75° C., and 60° C.

Wet Wipe Wetting Composition and Wet Wipes Containing the Same

One embodiment of the present invention is the production of wet wipescomprising the triggerable binder formulations and fibrous substrates.For wet wipes, the fibrous substrate may be in the form of a woven ornonwoven fabric; however, nonwoven fabrics may be more typical. Thefibrous substrate may be formed from relatively short fibers, such aswood pulp fibers. The minimum length of the fibers may depend on themethod selected for forming the fibrous substrate, such as a nonwovenfabric. Where the fibrous substrate is formed by a wet or dry method,the fiber length may range from about 0.1 millimeters to 15 millimeters.The fibrous substrate for use in the present invention may have arelatively low wet cohesive strength when it is not bonded together byan, adhesive or binder material. When such fibrous substrates are bondedtogether by a triggerable binder formulation, which loses its bondingstrength in tap water and in sewer water, the fibrous substrate maybreak up readily by the agitation provided by flushing and movingthrough the sewer pipes.

The finished wet wipes may be individually packaged, desirably in afolded condition, in a moisture and/or solvent proof envelope orpackaged in containers holding any desired number of sheets of wet wipesin a moisture/solvent-tight package with a wetting composition appliedto the wet wipe. The finished wet wipes may also be packaged as a rollof separable sheets of wet wipes in a moisture/solvent-proof containerholding any desired number of sheets of wet wipes on the roll with awetting composition applied to the wet wipes. The roll may be corelessand either hollow or solid. Coreless rolls, including rolls with ahollow center or without a solid center, may be produced with knowncoreless roll winders, including those of SRP Industry, Inc. located inSan Jose, Calif.; Shimizu Manufacturing located in Japan; and, thedevices discussed in U.S. Pat. No. 4,667,890, issued to Gietman on May26, 1987. Solid-wound coreless rolls may offer more product for a givenvolume and may be adapted for a wide variety of dispensers.

Relative to the weight of the dry fibrous substrate, the wet wipe maycontain from about 10 percent to about 500 percent of the wettingcomposition, more specifically from about 100 percent to about 400percent of the wetting composition, and even more specifically fromabout 200 percent to about 300 percent of the wetting composition. Thewet wipe may maintain its desired characteristics over the time periodsinvolved in warehousing, transportation, retail display and storage bythe consumer.

Various forms of impermeable envelopes and storage means for containingwet-packaged materials, such as wipes and towelettes and the like, arewell known in the art. Any of these may be employed in packaging the wetwipes of the present invention.

The wet wipes of the present invention are wetted with an solvent-basedwetting composition, which has one or more of the following properties:

-   -   (1) is compatible with the above-described triggerable binder        formulations of the present invention;    -   (2) enables the pre-moistened wipe to maintain its wet strength        during converting, storage and usage (including dispensing), as        well as, dispersibility in a toilet bowl;    -   (3) reduces tackiness of the wipe, and provides tactile        properties, such as skin glide and a “lotion-like feel”;    -   (4) acts as a vehicle to deliver cleansing, sanitizing, or        disinfecting benefits;    -   (5) acts as a vehicle to deliver “moist cleansing” and other        skin health benefits; and,    -   (6) provides for rapid evaporation and/or drying.

In one aspect of the present invention, the wetting composition maycontain an insolubilizing agent that maintains the strength of awater-dispersible triggerable binder formulation until theinsolubilizing agent is diluted with water, whereupon the strength ofthe water-dispersible triggerable binder formulation begins to decay.The water-dispersible triggerable binder formulation may be any of thetriggerable binder formulations of the present invention. Theinsolubilizing agent in the wetting composition may be a lower levelalcohol, glycol, ketone, or mixtures thereof which provides in-use andstorage strength to the water-dispersible triggerable binderformulation, and may be diluted in water to permit dispersion of thefibrous substrate as the triggerable binder formulation triggers to aweaker state. Examples of lower level alcohols, glycols, and ketones mayinclude, but are not limited to: methyl alcohol; ethyl alcohol; n-propylalcohol; isopropyl alcohol; n-butyl alcohol; sec-butyl alcohol;tert-butyl alcohol; ethylene glycol; 1,2 propandiol (propylene glycol);1,3 propane diol; acetone; methylethyl ketone; and, mixtures thereof.

Determination of a suitable lower level alcohol, glycol, ketone, ormixtures thereof may be conducted using the solubility. The solubilityof an amorphous polymer in a given solvent is governed by the Gibbs freeenergy of mixing given by Equation (1):ΔG _(m) =ΔH _(m) −TΔS _(m)  (1)ΔG_(m) is the free energy change of the system upon mixing. ΔH_(m) andΔS_(m) are the enthalpy and entropy change upon mixing, respectively,and T is the absolute temperature. When the free energy of mixing isless than zero (ΔG_(m)<0) for a given polymer and solvent (or solventmixture thereof), a single-phase system is obtained and mixing occursspontaneously. Since dissolution of a high molecular weight polymer isalmost always accompanied by an increase in entropy of the system(ΔS_(m)>0), the sign and magnitude of ΔH_(m) is generally the decidingfactor for solubility.

Solubility parameters, originally developed to describe enthalpy ofmixing with simple nonpolar solvents, have been extended to describe theinteractions of polymers and polar solvent. The enthalpy of mixing ofsuch systems is expressed in a form like Equation (2): $\begin{matrix}{{\Delta\quad H_{m}} = {{V\left( {\left( \frac{\Delta\quad E_{1}^{v}}{V_{1}} \right)^{\frac{1}{2}} - \left( \frac{\Delta\quad E_{2}^{v}}{V_{2}} \right)^{\frac{1}{2}}} \right)}^{2}\phi_{1}\phi_{2}}} & (2)\end{matrix}$V is the volume of the mixture, ΔE₁ ^(v) is the ideal energy ofvaporization of the solvent, and ΔE₂ ^(v) is the ideal or theoreticalenergy of vaporization of the polymer. V₁ and V₂ are the partial molarvolumes of the solvent and polymer, respectively. φ₁ and φ₂ are therespective volume fractions. The (ΔE_(i) ^(v)/V_(i)) terms represent“cohesive energy density” values and correspond to the energy ofvaporization per unit volume of a component under ideal conditions. Thesolubility parameter or Hildebrand parameter, δ, is defined as thesquare root of the cohesive energy density, given by Equation (3):$\begin{matrix}{\delta_{i} = \left( \frac{\Delta\quad E_{i}^{v}}{V_{i}} \right)^{\frac{1}{2}}} & (3)\end{matrix}$The solubility parameter describes the attractive strength between themolecules of a material and is sometimes referred to as an “internalcohesion parameter”. For the mixing of two substances to take place, thebreaking of these internal cohesive forces must occur.

Substituting the results from Equation (3) and Equation (2) intoEquation (1) and canceling the bulk volume term (V) yields the followingresult, where v₁ and v₂ are the relative volumes of the solvent andpolymer, respectively, as depicted in Equation (4):ΔG _(m)=((δ₁−δ₂)² v ₁ v ₂)−TΔS _(m)  (4)Equation (4) represents the thermodynamic basis for the old chemicalrule-of-thumb, “like dissolves like”. When δ₁=δ₂, the enthalpic termgoes to zero and the free energy of mixing is always negative. If thedifference is small, the entropic term may out weight the enthalpy andspontaneous mixing will still occur. If the difference in δ values islarge, then the magnitude of the enthalpic term will out-weigh theentropy gain and mixing will not occur. In such cases where thedifference in solubility parameters for a polymer-solvent combination islarge, the solvent is considered to be a “non-solvent” for the polymer.

The units of δ may be difficult to rationalize. They are generallyexpressed as units of MPa^(1/2) or (cal/cm³)^(1/2). One simple way tounderstand these units is to note that Equation (4) calls for a solutionin terms of a quantity of energy. It can be readily seen thatsubstitution of δ values in terms of (cal/cm³)^(1/2) or MPa^(1/2) intoEquation (4) results in a quantity of energy in terms of calories orjoules, respectively, after unit cancellation (1 MPa=1 kJ/m³). Forpurposes of the present work, (cal/cm³)^(1/2) units for δ will be used.

Finally, in the extension of solubility parameters to polar systems, oneshould recognize the presence and activity of hydrogen bonding. Hydrogenbonding forces may be much stronger than van der Waals and dipole forcesand may dominate the enthalpy of mixing. In general, completemiscibility may be only expected when the solubility parameter andhydrogen bonding character are similar. The contribution of hydrogenbonding applies to the solubility of polar vinyl polymers, such apolyacrylamide and polyvinyl pyrrolidone. In this study, numericalhydrogen bonding indices are assigned. Often, however, solvents areassigned to a hydrogen-bonding group: strong (s); moderate (m); and,poor (p). Direct comparison of physical properties of polymer-solventpairs based on δ values will usually be done within the same hydrogenbonding group.

A vast number of solvent solubility parameter values are available inthe Polymer Handbook, 4^(th) Edition, John Wiley & Sons, New York,(1999), the disclosure of which is incorporated by reference to theextent it is non-contradictory herewith. Table A shows the solubilityparameters and hydrogen bonding groups for selected solvents. Note thatall the solvents selected are strong hydrogen bonders except foracetone, which has moderate hydrogen bonding ability. Typically,miscibility with water is desirable for disposal in common waste-waterstreams, but other solvents may also be suitable. δ values for thesesolvents range from 14.5 to 9.9. Water, on the other hand, has a muchhigher value of 23.4, is a strong hydrogen bonder, and is known to be avery good solvent for many polymers with polar groups, hence the term“water-soluble polymers”.

A δ value for polyacrylamide homopolymer (PAM) of 21 (cal/cm³)^(1/2) hasbeen assigned for comparison. This also allows calculation of thecohesive energy difference parameter, (δ₁−δ₂)², for each solvent withPAM. These data are also presented in Table A. A solubility parameter isnot readily available for polyvinylamine/vinylamide resins. However,polyvinylformamide is a structural isomer and should be expected to havesimilar values through functional group contributions. Therefore,copolymers derived from this material should have similar solubilitybehavior as acrylamide copolymers and some license may be taken indiscussing their behavior generically as “polyacrylamide”, unlessspecific differences are being highlighted.

With decreasing δ value or increasing cohesive energy difference, thesolvents in Table A should become better non-solvents forpolyacrylamide. Therefore, fibrous substrates treated withpolyacrylamide and wetted with non-solvent should show high in-usestrength. Strength should somehow correlate with the non-solvency of thewetting fluid or δ value. In certain cases, it may be desirable to use amixture of one or more of the solvents with water. In these cases,solvency (or non-solvency) of the solvent mixture may be evaluated bycalculating a weighted average or “apparent” solubility parameter(δ_(1(app))) and properties of the fibrous substrate should governed bythe relative amounts of solvent and non-solvent in the solvent mixture.TABLE A Solubility parameter values and hydrogen bonding groups forselected solvents. Solubility Parameter, δ ({tilde over (δ)}₁ − δ₂)²H-Bonding Solvent ID (cal/cm³)^(1/2) PAM Group Water H₂O 23.4 5.8 sMethyl alcohol MeOH 14.5 42.3 s Ethyl alcohol EtOH 12.7 68.9 s Propyleneglycol PPG 12.6 70.6 s n-Propyl alcohol NPA 11.9 82.8 s Isopropylalcohol IPA 11.5 90.3 s n-Butyl alcohol NBA 11.4 92.6 s t-Butyl alcoholTBA 10.6 108.2 s Acetone ACE 9.9 123.2 m

The wetting composition may contain more than about 0.3 weight percentof the insolubilizing agent based on the total weight of the wettingcomposition for triggerable binder polymers or polymer formulations.Specifically, the wetting composition may contain from about 50 weightpercent to about 100 weight percent of the insolubilizing agent. Evenmore specifically, the wetting composition may contain from about 65weight percent to about 90 weight percent of an insolubilizing agent.More precisely, the wetting composition may contain from about 70 weightpercent to about 90 weight percent of the insolubilizing agent.

The wetting composition of the present invention may further comprise avariety of additives compatible with the insolubilizing agent and thewater-dispersible triggerable binder formulation, such that the strengthand dispersibility functions of the wet wipe are not jeopardized.Suitable additives in the wetting composition include, but are notlimited to, the following additives: chelators; odor control agents;detackifying agents to reduce the tackiness of the triggerable binderformulation; particulates; antimicrobial agents; preservatives; wettingagents and cleaning agents, such as detergents, surfactants, and somesilicones; emollients; humectants; surface feel modifiers for improvedtactile sensation (e.g., lubricity) on the skin; fragrance; fragrancesolubilizers; opacifiers; fluorescent whitening agents; stabilizers;oxidizers; UV absorbers; pharmaceuticals; and, pH control agents, suchas malic acid and potassium hydroxide.

Examples of wetting compositions are described in U.S. Pat. No.5,145,663, issued to Simmons on Sep. 8, 1992 and U.S. Pat. No.5,441,723, issued, to Simmons on Aug. 15, 1995, the disclosures of whichare incorporated by reference to the extent that they arenon-contradictory herewith.

Additional Additives

Odor Control Additives

Suitable odor control additives for use in the wetting composition andwet wipes of the present invention may include, but are not limited to:zinc salts; talc powder; encapsulated perfumes (including microcapsules,macrocapsules, and perfume encapsulated in liposomes, vesicles, ormicroemulsions); chelants, such as ethylenediamine tetra-acetic acid;zeolites; activated silica, activated carbon granules or fibers;activated silica particulates; polycarboxylic acids, such as citricacid; cyclodextrins and cyclodextrin derivatives; chitosan or chitin andderivatives thereof; oxidizing agents; antimicrobial agents, includingsilver-loaded zeolites (e.g., those of BF Technologies, located inBeverly, Mass., sold under the trademark HEALTHSHIELDTM); triclosan;kieselguhr; and, mixtures thereof. In addition to controlling odor fromthe body or body wastes, odor control strategies may also be employed tomask or control any odor of the treated fibrous substrate. The wettingcomposition may contain less than about 5 weight percent of odor controladditives based on the total weight of the wetting composition. Morespecifically, the wetting composition may contain from about 0.01 weightpercent to about 2 weight percent of odor control additives. Even morespecifically, the wetting composition may contain from about 0.03 weightpercent to about 1 weight percent of odor control additives.

In one embodiment of the present invention, the wetting compositionand/or wet wipes may comprise derivatized cyclodextrins, such ashydroxypropyl beta-cyclodextrin in solution, which remain on the skinafter wiping and provide an odor-absorbing layer. In other embodimentsof the present invention, the odor source may be removed or neutralizedby application of an odor-control additive, exemplified by the action ofa chelant that binds metal groups necessary for the function of manyproteases and other enzymes that commonly produce an odor. Chelating themetal group interferes with the enzyme's action and decreases the riskof malodor in the wet wipe product.

Principles for the application of chitosan or chitin derivatives tononwoven webs and cellulosic fibers are described by S. Lee et al. in“Antimicrobial and Blood Repellent Finishes for Cotton and NonwovenFabrics Based on Chitosan and Fluoropolymers,” Textile Research Journal,69(2); 104-112, February 1999.

Microparticulates

The wetting composition of the present invention may be further modifiedby the addition of solid particulates or microparticulates. Suitableparticulates may include, but are not limited to: mica, silica, alumina,calcium carbonate, kaolin, talc, and zeolites. The particulates may betreated with stearic acid or other additives to enhance the attractionor bridging of the particulates to the triggerable binder formulation,if desired. Also, two-component microparticulate systems, commonly usedas retention aids in the papermaking industry, may also be used. Suchtwo-component microparticulate systems generally comprise a colloidalparticle phase, such as silica particles, and a water-soluble cationicpolymer for bridging the particles to the fibers of the fibroussubstrate to be formed. The presence of particulates in the wettingcomposition may serve one or more useful functions, such as: (1)increasing the opacity of the wet wipes; (2) modifying the rheology orreducing the tackiness of the wet wipe; (3) improving the tactileproperties of the wet wipe; or, (4) delivering desired agents to theskin via a particulate carrier, such as a porous carrier or amicrocapsule. The wetting composition may contain less than about 25weight percent of particulate based on the total weight of the wettingcomposition. More specifically, the wetting composition may contain fromabout 0.05 weight percent to about 10 weight percent ofmicroparticulate. Even more specifically, the wetting composition maycontain from about 0.1 weight percent to about 5 weight percent ofmicroparticulate.

Microcapsules and Other Delivery Vehicles

Microcapsules and other delivery vehicles may also be used in thewetting composition of the present invention to provide skin-careagents; medications; comfort promoting agents, such as eucalyptus;perfumes; skin care agents; odor control additives; vitamins; powders;and, other additives to the skin of the user. Specifically, the wettingcomposition may contain up to about 25 weight percent of microcapsulesor other delivery vehicles based on the total weight of the wettingcomposition. More specifically, the wetting composition may contain fromabout 0.05 weight percent to about 10 weight percent of microcapsules orother delivery vehicles. Even more specifically, the wetting compositionmay contain from about 0.2 weight percent to about 5.0 weight percent ofmicrocapsules or other delivery vehicles.

Microcapsules and other delivery vehicles are well known in the art. Forexample, POLY-PORE® E200, commercially available from ChemdalCorporation located in Arlington Heights, Ill., may be a delivery agentcomprising soft, hollow spheres that can contain an additive at over 10times the weight of the delivery vehicle. Additives that may be usedwith POLY-PORE® E200 include, but are not limited to: benzyl peroxide,salicylic acid, retinol, retinyl palmitate, octyl methoxycinnamate,tocopherol, silicone compounds (DC 435), and mineral oil. Anotherdelivery vehicle that may be used in the present invention is asponge-like material commercially available under the trade designationof POLY-PORE® L200 from Chemdal Corporation, with silicone (DC 435) andmineral oil. Other delivery systems may include cyclodextrins and theirderivatives, liposomes, polymeric sponges, and spray-dried starch.

Additives present in microcapsules may be isolated from the environmentand the other agents in the wetting composition until the wet wipe isapplied to the skin, whereupon the microcapsules break and deliver theirload to the skin or other surfaces.

Preservatives and Anti-Microbial Agents

The wetting composition of the present invention may also containpreservatives and/or anti-microbial agents for cleaning and/orsanitizing uses. Several preservatives and/or anti-microbial agents,such as Mackstat H 66 commercially available from McIntyre Group locatedin Chicago, Ill., may prevent bacteria and mold growth. Otherpreservatives and anti-microbial agents may include, but are not limitedto: DMDM hydantoin, e.g., commercially available under the tradedesignation of Glydant Plus™ from Lonza, Inc. located in Fair Lawn,N.J.; iodopropynyl butylcarbamate; Kathon commercially available fromRohm and Hass located in Philadelphia, Pa.; methylparaben;propylparaben; 2-bromo-2-nitropropane-1,3-diol; benzoic acid;benzalkonium chloride; benzethonium chloride; and, the like. The wettingcomposition may contain less than about 2 weight percent on an activebasis of preservatives and/or anti-microbial agents based on the totalweight of the wetting composition. More specifically, the wettingcomposition may contain from about 0.01 weight percent to about 1 weightpercent of preservatives and/or anti-microbial agents. Even morespecifically, the wetting composition may contain from about 0.01 weightpercent to about 0.5 weight percent of preservatives and/oranti-microbial agents. Further discussion regarding preservatives and/oranti-microbial agents may be found in Disinfection, Sterilization, andPreservation, 4^(th) Edition, Lea & Frebiger, (1991), the disclosure ofwhich is incorporated by reference to the extent it is non-contradictoryherewith.

Wetting Agents and Cleaning Agents

A variety of wetting agents and/or cleaning agents may be used in thewetting composition of the present invention. Suitable wetting agentsand/or cleaning agents may include, but are not limited to; detergentsand nonionic, amphoteric, cationic, and anionic surfactants. The wettingcomposition may contain less than about 3 weight percent of wettingagents and/or cleaning agents based on the total weight of the wettingcomposition. More specifically, the wetting composition may contain fromabout 0.01 weight percent to about 2 weight percent of wetting agentsand/or cleaning agents. Even more specifically, the wetting compositionmay contain from about 0.1 weight percent to about 0.5 weight percent ofwetting agents and/or cleaning agents. Suitable cationic surfactants mayinclude, but are not limited to, quaternary ammonium alkyl halides likecetyl trimethyl ammonium chloride and cetyl trimethyl ammonium bromide.

Amino acid-based surfactant systems, such as those derived from aminoacids L-glutamic acid and other natural fatty acids, may offer pHcompatibility to human skin and good cleansing power, while beingrelatively safe and providing improved tactile and moisturizationproperties compared to other anionic surfactants. One function of thesurfactant may be to improve wetting of the dry fibrous substrate withthe wetting composition. Another function of the surfactant may be todisperse bathroom soils when the wet wipe contacts a soiled area and toenhance their absorption into the fibrous substrate. The surfactant mayassist in make-up removal, general personal cleansing, hard surfacecleansing, odor control, and the like. One commercially availableexample of an amino-acid based surfactant is acylglutamate, marketedunder the trade designation of Amisoft from Ajinomoto Corporationlocated in Tokyo, Japan.

Suitable non-ionic surfactants may include, but are not limited to, thecondensation products of ethylene oxide with a hydrophobic (oleophilic)polyoxyalkylene base formed by the condensation of propylene oxide withpropylene glycol. The hydrophobic portion of these compounds may have amolecular weight sufficiently high so as to render it water-insoluble.The addition of polyoxyethylene moieties to this hydrophobic portionincreases the water-solubility of the molecule as a whole, and theliquid character of the product may be retained up to the point wherethe polyoxyethylene content is about 50% of the total weight of thecondensation product. Examples of compounds of this type includecommercially available Pluronic surfactants from BASF WyandotteCorporation located in Wyandotte, Mich., especially those in which thepolyoxypropylene ether has a molecular weight of about 1500 to about3000 and the polyoxyethylene content is about 35% to about 55% of themolecule by weight, i.e. Pluronic L-62.

Other useful nonionic surfactants may include, but are not limited to,the condensation products of C₈ to C₂₂ alkyl alcohols with 2 to 50 molesof ethylene oxide per mole of alcohol. Examples of compounds of thistype may include the condensation products of C₁₁ to C₁₅ secondary alkylalcohols with 3 to 50 moles of ethylene oxide per mole of alcohol, whichare commercially available under the trade designation of thePoly-Tergent SLF series from Olin Chemicals located in Baltimore City,Md. or the TERGITOL® series from Union Carbide located in Danbury,Conn.; i.e., TERGITOL® 25-L-7, which is formed by condensing about 7moles of ethylene oxide with a C₁₂ to C₁₅ alkanol.

Other nonionic surfactants, which may be employed in the wettingcomposition of the present invention, may include the ethylene oxideesters of C₆ to C₁₂ alkyl phenols such as (nonylphenoxy)polyoxyethyleneether. Esters prepared by condensing about 8 to 12 moles of ethyleneoxide with nonylphenol, i.e. the IGEPAL® CO series commerciallyavailable from GAF Corporation located in Wayne, N.J. may be used in thewetting composition of the present invention.

Further non-ionic surface active agents may include, but are not limitedto, alkyl polyglycosides (APG) derived as a condensation product ofdextrose (D-glucose) and a straight or branched chain alcohol. Theglycoside portion of the surfactant may provide a hydrophile having highhydroxyl density, which enhances water solubility. Additionally, theinherent stability of the acetal linkage of the glycoside provideschemical stability in alkaline systems. Furthermore, unlike somenon-ionic surface active agents, alkyl polyglycosides have no cloudpoint, allowing one to formulate without a hydrotrope, and these arevery mild, as well as readily biodegradable non-ionic surfactants. Thisclass of surfactants is commercially available from Henkel Corporationlocated in Ambler, Pa. under the trade designations of Glucopon 220,Glucopon 225 and Glucopon 425.

Silicones are another class of wetting agents that may be available inpure form, or as microemulsions, macroemulsions, and the like. Onenon-ionic surfactant group is the silicone-glycol copolymers. Thesesurfactants may be prepared by adding poly(lower)alkylenoxy chains tothe free hydroxyl groups of dimethylpolysiloxanols and are commerciallyavailable from the Dow Corning Corporation located in Midland, Mich.under the trade designations of Dow Corning 190 and Dow Corning 193surfactants (CTFA name: dimethicone copolyol). These surfactants mayfunction, with or without any volatile silicones used as solvents, tocontrol foaming produced by the other surfactants, and also may impart ashine to metallic, ceramic, and glass surfaces.

Anionic surfactants may also be used in the wetting compositions of thepresent invention. Anionic surfactants may be useful due to their highdetergency include anionic detergent salts having alkyl substituents of8 to 22 carbon atoms such as the water-soluble higher fatty acid alkalimetal soaps, e.g., sodium myristate and sodium palmitate. One class ofanionic surfactants encompasses the water-soluble sulfated andsulfonated anionic alkali metal and alkaline earth metal detergent saltscontaining a hydrophobic higher alkyl moiety (typically containing fromabout 8 to 22 carbon atoms) such as salts of higher alkyl mono orpolynuclear aryl sulfonates having from about 1 to 16 carbon atoms inthe alkyl group, with examples commercially available under the tradedesignation of the Bio-Soft series, i.e. Bio-Soft D-40 from StepanChemical Co. located in Northfield, Ill.

Other useful classes of anionic surfactants may include, but are notlimited to: sulfated higher fatty acid monoglycerides such as the sodiumsalt of the sulfated monoglyceride of cocoa oil fatty acids and thepotassium salt of the sulfated monoglyceride of tallow fatty acids;alkali metal salts of sulfated fatty alcohols containing from about 10to 18 carbon atoms (e.g., sodium lauryl sulfate and sodium stearylsulfate); sodium C₁₄ to C₁₆-alphaolefin sulfonates such as the Bio-Tergeseries commercially available from Stepan Chemical Co.; alkali metalsalts of sulfated ethyleneoxy fatty alcohols (the sodium or ammoniumsulfates of the condensation products of about 3 moles of ethylene oxidewith a C₁₂ to C₁₅ n-alkanol, i.e., the Neodol ethoxysulfatescommercially available from Shell Chemical Co. located in Houston, Tex.;alkali metal salts of higher fatty esters of low molecular weightalkylol sulfonic acids, e.g. fatty acid esters of the sodium salt ofisothionic acid and the fatty ethanolamide sulfates; the fatty acidamides of amino alkyl sulfonic acids, e.g., lauric acid amide oftaurine; as well as numerous other anionic organic surface active agentssuch as sodium xylene sulfonate, sodium naphthalene sulfonate, sodiumtoulene sulfonate; and, mixtures thereof.

A further useful class of anionic surfactants may includes the8-(4-n-alkyl-2-cyclohexenyl)-octanoic acids, wherein the cyclohexenylring is substituted with an additional carboxylic acid group. Thesecompounds or their potassium salts, are commercially available fromWestvaco Corporation located in Meriden, Conn. under the tradedesignations of Diacid 1550 or H-240. In general, these anionic surfaceactive agents may be employed in the form of their alkali metal salts,ammonium or alkaline earth metal salts.

Surface Feel Modifiers

Surface feel modifiers may be used to improve the tactile sensation(e.g., lubricity) of the skin during use of the cleaning or personalcare product. Suitable surface feel modifiers include, but are notlimited to, commercial debonders and softeners, such as the softenersused in the art of tissue making including quaternary ammonium compoundswith fatty acid side groups, silicones, waxes, and the like. Quaternaryammonium compounds that may have utility as softeners are disclosed inU.S. Pat. No. 3,554,862, issued to Hervey et al. on Jan. 12, 1971; U.S.Pat. No. 4,144,122, issued to Emanuelsson et al. on Mar. 13, 1979; U.S.Pat. No. 5,573,637, issued to Ampulski et al. on Nov. 12, 1996; and,U.S. Pat. No. 4,476,323, issued to Hellsten et al. on Oct. 9, 1984, thedisclosures of which are incorporated by reference to the extent thatthey are non-contradictory herewith. The wetting composition may containless than about 2 weight percent of surface feel modifiers based on thetotal weight of the wetting composition. More specifically, the wettingcomposition may contain from about 0.01 weight percent to about 1 weightpercent of surface feel modifiers. Even more specifically, the wettingcomposition may contain from about 0.01 weight percent to about 0.05weight percent of surface feel modifiers.

Fragrances

A variety of fragrances may be used in the wetting composition of thepresent invention. The wetting composition may contain less than about 2weight percent of fragrances based on the total weight of the wettingcomposition. More specifically, the wetting composition may contain fromabout 0.01 weight percent to about 1 weight percent of fragrances. Evenmore specifically, the wetting composition may contain from about 0.01weight percent to about 0.05 weight percent of fragrances.

Fragrance Solubilizers Further, a variety of fragrance solubilizers maybe used in the wetting composition of the present invention. Suitablefragrance solubilizers may include, but are not limited to: polysorbate20; propylene glycol; ethanol; isopropanol; diethylene glycol monoethylether; dipropylene glycol; diethyl phthalate; triethyl citrate; AmeroxolOE-2 commercially available from Amerchol Corporation located inMidland, Mich.; Brij 78 and Brij 98 commercially available from ICISurfactants located in Wilmington, Del.; Arlasolve 200 commerciallyavailable from ICI Surfactants; Calfax 16L-35 commercially availablefrom Pilot Chemical Co. located in Santa Fe Springs, Calif.; CapmulPOE-S commercially available from Abitec Corporation located inColumbus, Ohio; Finsolv SUBSTANTIAL commercially available from Finetexlocated in Elmwood Park, N.J.; and, the like. The wetting compositionmay contain less than about 2 weight percent of fragrance solubilizersbased on the total weight of the wetting composition. More specifically,the wetting composition may contain from about 0.01 weight percent toabout 1 weight percent of fragrance solubilizers. Even morespecifically, the wetting composition may contain from about 0.01 weightpercent to about 0.05 weight percent of fragrance solubilizers.

Opacifiers

Suitable opacifiers may include, but are not limited to, titaniumdioxide or other minerals or pigments, and synthetic opacifiers, such asREACTOPAQUE® particles commercially available from Sequa Chemicals, Inc.located at Chester, S. C. The wetting composition may contain less thanabout 2 weight percent of opacifiers based on the total weight of thewetting composition. More specifically, the wetting composition maycontain from about 0.01 weight percent to about 1 weight percent ofopacifiers. Even more specifically, the wetting composition may containfrom about 0.01 weight percent to about 0.05 weight percent ofopacifiers.

pH Control Agents

pH control agents for use in the wetting composition of the presentinvention may include, but are not limited to; malic acid; citric acid;hydrochloric acid; acetic acid; sodium hydroxide; potassium hydroxide;and, the like. An appropriate pH range minimizes the amount of skinirritation resulting from the wetting composition on the skin. The pHrange of the wetting composition may range from about 3.5 to about 6.5.More specifically, the pH range of the wetting composition may rangefrom about 4 to about 6. The overall pH of the wet wipe product; i.e.,the complete wet wipe product including the fibrous substrate portionand the wetting composition portion, may range from about 4.5 to about5.5; more specifically, about 5.0. The wetting composition may containless than about 2 weight percent of a pH adjuster based on the totalweight of the wetting composition. More specifically, the wettingcomposition may contain from about 0.01 weight percent to about 1 weightpercent of a pH adjuster. Even more specifically, the wettingcomposition may contain from about 0.01 weight percent to about 0.05weight percent of a pH adjuster.

It should be noted that the above-described wetting compositions of thepresent invention may be used with any one of the above-describedtriggerable binder compositions of the present invention. Further, theabove-described wetting compositions of the present invention may beused with any other binder composition, including conventional bindercompositions, or with any known fibrous or absorbent substrate, whetherdispersible or not.

Method of Making Wet Wipes

The wet wipes of the present invention may be made in several ways. Inone embodiment of the present invention, the triggerable binderformulation may be applied to a fibrous substrate as part of an aqueoussolution or suspension, wherein subsequent drying is needed to removethe water and promote binding of the fibers within the fibroussubstrate. In particular, during drying, the triggerable binderformulation migrates to the crossover points of the fibers and becomesactivated as a triggerable binder formulation in those regions, thusproviding acceptable strength to the fibrous substrate. By way ofexample, the following steps are provided and may be applied:

-   -   1. Providing an absorbent fibrous substrate that is not highly        bonded (e.g., an unbonded airlaid, a tissue web, a carded web,        fluff pulp, etc.);    -   2. Applying a triggerable binder formulation to the fibrous        substrate, typically in the form of a liquid, suspension, or        foam;    -   3. Drying the fibrous substrate to promote bonding of the fibers        within the fibrous substrate;    -   4. Applying a wetting composition to the fibrous substrate        thereby providing a wetted product; and,    -   5. Placing the wetted product in roll form or in a stack and        packaging the wetted product.

Application of the triggerable binder formulation to the fibroussubstrate may be accomplished by means of spray application; foamapplication; immersion in a bath; curtain coating; coating and meteringwith a wire-wound rod; passage of the fibrous substrate through aflooded nip; contact with a pre-metered wetted roll coated with thetriggerable binder formulation; by pressing the fibrous substrateagainst a deformable carrier containing the triggerable binderformulation such as a sponge or felt to effect transfer into the fibroussubstrate; printing such as gravure, inkjet, or flexographic printing;and, any other means known to one skilled in the art. In thealternative, wet-end application is acceptable.

Without wishing to be bound by theory, it is believed that a drying stepafter application of the triggerable binder formulation and beforeapplication of the wetting composition may enhance bonding of the fiberswithin a fibrous substrate by driving the triggerable binder formulationto fiber crossover points as moisture is driven off, thus promotingefficient use of the triggerable binder formulation. However, in analternative method, the drying step discussed above may be skipped, andthe triggerable binder formulation may be applied to the fibroussubstrate followed by application of the wetting composition withoutsignificant intermediate drying. In one embodiment of this method, thetriggerable binder formulation may selectively adhere to the fibers,permitting excess water to be removed in an optional pressing stepwithout a significant loss of the triggerable binder formulation fromthe fibrous substrate. In another embodiment of this method, nosignificant water removal need occur prior to application of the wettingcomposition. In yet another alternative embodiment of this method, thetriggerable binder formulation and the wetting composition may beapplied simultaneously to the fibrous substrate, optionally withsubsequent addition of additives or insolubilizing agents to furtherrender the triggerable binder formulation insoluble.

The present invention may be further illustrated by the followingexamples, which are not to be construed in any way as imposinglimitations upon the scope thereof. On the contrary, it is to be clearlyunderstood that resort may be had to various other embodiments,modifications, and equivalents thereof which, after reading thedescription herein, may suggest themselves to those skilled in the artwithout departing from the spirit of the present invention and/or thescope of the appended claims.

EXAMPLE 1

Wetting Composition Preparation

ACS reagent grade or better of isopropanol (IPA), acetone(ACE), t-butylalcohol (TBA), n-butyl alcohol (NBA), n-propanol (NPA), ethanol (EtOH)or methanol (MeOH) were used in formulating the wetting solutions usedin the following examples. The concentrations of these insolubilizingagents in the wetting compositions ranged between 60% and 100% (neat).Where the concentration of the insolubilizing agents in the wettingcompositions was below 100%, insolubilizing agent was combined withdeionized water.

Fibrous Substrate Sample Preparation

Two different fibrous substrates were used to evaluate the performanceof the triggerable binder formulation: UCTAD tissue and thermally-bondedair-laid nonwoven.

UCTAD Tissue

An uncreped through-air dried(UCTAD) tissue fibrous substrate with abasis weight of about 50 gsm and a caliper of about 1.3 mm was used toevaluate samples of the triggerable binder formulations. Eucalyptus woodpulp fibers are commercially available from Aracruz located in theBrazilian states of Espirito Santo, Rio Grande do Sul and Eunapolis.LL-19 wood pulp fibers are commercially available from Kimberly-ClarkCorporation located in Neenah, Wis. These fibers were used to form thefibrous substrates. The eucalyptus and LL-19 wood pulp fibers weredispersed into water to form an eucalyptus pulp fiber slurry and a LL-19pulp fiber slurry. A 3-layer headbox was utilized to deposit the pulpfiber slurries in a 30/40/30 split of eucalyptus/LL-19/eucalyptus woodpulp fibers into a fibrous substrate. The substrate was rush-transferredto a transfer fabric(T807-1 from Voith Fabrics of Appleton, Wis.). Thetransfer fabric was traveling 28-30 percent slower than the formingfabric using a vacuum shoe to assist the transfer. At a second vacuumshoe-assisted transfer, the substrate was transferred and wet-moldedonto the throughdrying fabric (T1203-8 from Voith Fabrics of Appleton,Wis.). The sheet was dried with a throughdryer operating at atemperature of approximately 290° F. Targeted ranges of geometric meantensile(GMT) and tensile ratio were 1500-2000 and 1.2-1.5, respectively.The UCTAD fibrous substrate had no residual wet strength in water.

Thermally-bonded Air-laid Nonwoven

A weak, thermally-bonded air-laid (TBAL) nonwoven fibrous substrate wasfabricated using Weyerhauser NF405 wood pulp fibers and KoSA T-255binder fibers. The T-255 binder fibers had a polyester core and apolyethylene sheath that melts at about 130° C. The air-laid fibroussubstrate was formed using about 4% T-255 binder fibers and thermallybonded above the melting temperature of the polyethylene sheath. TheTBAL fibrous substrate samples have an average basis weight of about 51gsm and an average caliper of about 1.0 mm. The TBAL fibrous substratesamples have a residual CD wet tensile strength of about 30 g/inch inwater. Unless otherwise noted, the data for the TBAL fibrous substratesamples have been corrected for this residual wet strength. Theapplication and drying methods used for the treatments of thetriggerable binder formulation are those described above for the UCTADfibrous substrate samples.

Topical Application Method for Triggerable Binder Formulation

A uniform and consistent amount of each sample of triggerable binderformulation was applied to the fibrous substrate via a pressurizedhandsheet spray unit. This handsheet spray unit is designed to closelyresemble the operation of a commercial air-laid machine using liquid oremulsion binders, but on a smaller pilot scale. The handsheet spray unitis enclosed in a small-framed housing, which may be placed, under alaboratory hood. The handsheet spray unit has a stationary sample holdersection (10″×13″) in the center of the unit and a moveable spray headerdirectly over the sample holder section. A vacuum box is installed underthe sample holder section to help draw the triggerable binderformulation into the fibrous substrate during the application process.The fibrous substrate sample is placed on the vacuum box and the sprayhead is moved across the fibrous substrate sample as the triggerablebinder formulation is sprayed in a flat V-shaped pattern. Thetriggerable binder formulation is contained in a pressurized storagevessel located outside of the spray cabinet and is delivered to thespray nozzles via high pressure flexible tubing. The spray header withits spray nozzle assembly (commercially available from Spraying SystemsCompany located at Wheaton, Ill.) is moved over the sample by means of abelt driven slide assembly, providing the desired application uniformityand speed. The spray header may be operated at speeds close to 180 fpmand the spray atomization pressure could be set as high as 200 psig.Approximately one half of the desired weight of the triggerable binderformulation is applied to the first side of each fibrous substratesample. Each fibrous substrate sample is then manually turned over andthe remaining desired weight of the triggerable binder formulation isapplied to the second side. The fibrous substrate sample is manuallyremoved and dried in a Werner Mathis, Model LTV Through-Air Dryer (TAD)at 193° C. for about 20 seconds to about 40 seconds.

In-use Tensile Strength and Disposal Strength Testing

A SinTech 1/D tensile tester with Testworks 3.03 version software isused for all sample testing. A 100 Newton load cell with pneumatic gripsis utilized. A gauge length of 2 inch and a crosshead speed of 12inch/minute are employed. The peak load values (in g/in.) of samplereplicates are recorded and averaged and reported as machine-directionwet tensile strength (MDWT) or cross-deckle wet tensile strength (CDWT),depending on how the measurement was made.

The in-use strength of each fibrous substrate sample is simulated bysoaking 1 inch by 4.5 inch strip fibrous substrate samples in an excessof wetting composition containing the desired insolubilizing agent. Thefibrous substrate samples are allowed to equilibrate for at least 12hours before measurements of the tensile strength of each fibroussubstrate samples are taken. The disposal strength or dispersibility isassessed by transferring the fibrous substrate samples treated as“in-use” into an excess (typically 500 mL for 4 to 8 strips of fibroussubstrate samples) of deionized water or hard water of specifiedhardness level (as metal ion) and allowing the fibrous substrate samplesto soak for the indicated amount of time before the tensile strength ofeach fibrous substrate sample is measured. In cases where a soakedfibrous substrate sample is too weak to be handled or to allowmeasurements of the tensile strength to be taken, a value of zero isrecorded for the peak load of the fibrous substrate sample.

Results

A non-crosslinking cationic polyacrylamide polymer, commerciallyavailable under the trade designation of Baystrength® 711 from BayerCorporation located in Pittsburgh, Pa., was evaluated as a triggerablebinder formulation on the UCTAD and TBAL fibrous substrate samples asdescribed above. Unless otherwise stated, the Baystrength® 711 as usedherein was a solution of 5% solids. The Baystrength® 711 polymer wasapplied to the fibrous substrate samples as described above. Thetriggerable binder formulation add-on level for each fibrous substratesample was 5 wt %. The treated fibrous substrate samples were allowed toequilibrate for in-use tensile strength measurements, as describedabove, in 100% and 65 wt % isopropyl alcohol (IPA) wetting compositions.The tensile strength of the treated fibrous substrate samples ispresented in Table 1. TABLE 1 Performance of Baystrength ® 711 polymerat 5 wt % triggerable binder formulation add-on level on TBAL and UCTADfibrous substrates in IPA wetting compositions. CDWT (g/in.) % IPA CDWT(g/in.) 10 min. Code (overnight soak) Basesheet In-use Std. Dev. HardWater Std. Dev. 8635-47-1 100 UCTAD 944 35 0 — 8635-47-2 65 UCTAD 232 3513 4 8635-47-3 100 TBAL 425 138 0 — 8635-47-4 65 TBAL 84 8 0 —As used herein, the phrase “overnight soak” means a soak of about 16 toabout 24 hours.

As shown in Table 1, the in-use tensile strength of the fibroussubstrate samples depends on fibrous substrate type and the compositionof the wetting composition. The UCTAD fibrous substrate sample showedsignificant In-use tensile strength in the 100% IPA wetting composition,possibly due to its inherent hydrogen bonding (about 325 g/in). However,the in-use tensile strength of the UCTAD fibrous substrate sample islower in the 65% IPA wetting composition, possibly due to the high watercontent. Higher in-use strength may be achieved in both fibroussubstrate types by choosing a wetting composition having a higheralcohol content. Dispersibility or disposal strength, as indicate by 10minute soaks in 200 ppm hard water (as metal ion), is very good for bothfibrous substrate types.

Two wetting compositions having antiseptic and disinfecting propertieswere formulated. The Baystrength® 711 polymer was applied to the fibroussubstrate samples as described above. The triggerable binder formulationadd-on level for each fibrous substrate sample was 5 wt %. The treatedfibrous substrate samples were allowed to equilibrate for in-use tensilestrength measurements in the formulated wetting compositions A and B.The in-use tensile strength of the treated fibrous substrate samples arepresented in Table 2. TABLE 2 Performance of Baystrength ® 711 polymerat 5 wt % triggerable binder formulation add-on level on TBAL and UCTADfibrous substrates in formulated wetting compositions A and B. CDWT(g/in.) Solution CDWT (g/in.) 10 min. Code (overnight soak) BasesheetIn-use Std. Dev. Hard Water Std. Dev. 8635-50-1 A UCTAD 375 28 19 78635-50-2 A TBAL 175 52 2 5 8635-50-3 B UCTAD 704 49 9 11 8635-50-4 BTBAL 463 40 1 5 Solution A: 65% IPA Solution B: 75% IPA 8% Propyleneglycol 12% Propylene glycol 27% Water 13% Water

As shown in Table 2, the in-use tensile strength of the treated fibroussubstrate samples depends on the fibrous substrate type and thecomposition, namely the water content, in the wetting composition. Thedispersibility or disposal strength for both fibrous substrate types isgood.

EXAMPLE 2

An anionic polyacrylamide polymer, commercially available under thetrade designation of Baystrength® 85 from Bayer Corporation, wasevaluated as a triggerable binder formulation on the UCTAD and TBALfibrous substrate samples as described above. The Baystrength® 85polymer was applied to the fibrous substrate samples as described above.The triggerable binder formulation add-on level for each fibroussubstrate sample ranged from 1.8 wt % to 10 wt %. The treated fibroussubstrate samples were allowed to equilibrate for in-use tensilestrength measurements, as described above, in wetting compositionshaving an IPA content that ranged from 65% to 100%. Dry treated fibroussubstrate samples were also tested for in-use tensile strength. Thein-use tensile strength of the treated fibrous substrate samples, wetand dry, is presented in Table 3. The dispersibility or disposalstrength of the treated fibrous substrate samples for 10 minute and 30minute soaks in 200 ppm hard water are also presented in Table 3. TABLE3 Performance of Baystrength ® 85 polymer at various triggerable binderformulation add-on levels on TBAL and UCTAD fibrous substrates in IPAwetting compositions. CDWT (g/in.) CDWT (g/in.) % IPA CDWT (g/in.) 10min. 30 min. Code % Binder overnight soak Basesheet In-use Std. Dev.Hard Water Std. Dev. Hard Water Std. Dev. 1 1.8 Dry UCTAD 1165 72 — — —— 2 1.8 100  UCTAD 931 45 0 — 0 — 3 1.8 90 UCTAD 572 136 0 — 0 — 4 1.880 UCTAD 347 98 0 — 0 — 5 1.8 65 UCTAD 155 43 0 — 0 — 6 5.0 Dry UCTAD1741 71 — — — — 7 5.0 100  UCTAD 1109 204 0 — 0 — 8 5.0 90 UCTAD 1090223 0 — 0 — 9 5.0 80 UCTAD 617 212 0 — 0 — 10 5.0 65 UCTAD 223 83 0 — 0— 11 6.9 Dry UCTAD 1546 139 — — — — 12 6.9 90 UCTAD 842 288 0 — 0 — 136.9 80 UCTAD 783 222 0 — 0 — 14 6.9 65 UCTAD 324 56 0 — 0 — 15 6.9 50UCTAD 117 21 0 — 0 — 16 7.6 Dry TBAL 547 83 — — — — 17 7.6 90 TBAL 29167 4 14 0 0 18 7.6 80 TBAL 204 94 14  29 29  0 19 7.6 65 TBAL 34 27 — —— — 20 10 Dry TBAL 936 266 — — — — 21 10 100  TBAL 582 228 28  14 20  622 10 90 TBAL 633 43 8  4 6 36  23 10 80 TBAL 316 117 14   9 10  4 24 1065 TBAL 51 17 22   9 13  5

As shown in Table 3, a broad range of in-use tensile strength anddisposal strength may be achieved by the choice of the fibrous substratetype and the composition of the wetting composition.

EXAMPLE 3

An UCTAD fibrous substrate sample having a basis weight of about 45 gsmand a caliper of about 1.3 mm commercially available from Kimberly-ClarkCorporation, was used for evaluation of the Baystrength® 85 polymer as atriggerable binder formulation. This UCTAD fibrous substrate samplepossesses a residual wet strength of about 40 gsm in water. The resultspresented in Table 4 were not corrected for residual wet strength of theUCTAD fibrous substrate samples in this example. The Baystrength® 85polymer was applied to the fibrous substrate samples as described above.The triggerable binder formulation add-on level for each fibroussubstrate sample ranged from 2 wt % to 5 wt %. The in-use tensilestrength and disposal strength for the treated fibrous substrate sampleswere evaluated as described in Example 1, with the exception that 100ppm hard water (as metal ion) was utilized for soak tests. The treatedfibrous substrate samples were allowed to equilibrate for in-use tensilestrength measurements, as described above, in wetting compositionshaving an IPA content ranging from 65% to 100%, an ethanol (EtOH)content ranging from 80% to 100%, or a methanol (MeOH) content of 100%.The treated fibrous substrate samples were soaked in the hard water fordisposal strength measurements for 10 minutes and 30 minutes. The in-usetensile strength and disposal strength measurements of the treatedfibrous substrate samples are presented in Table 4. TABLE 4 Performanceof Baystrength ® 85 polymer at various triggerable binder formulationadd-on levels on UCTAD fibrous substrate in various wettingcompositions. CDWT (g/in.) Binder % Solvent > 65% IPA 80% IPA 90% IPA100% IPA 80% EtOH 100% EtOH 100% MeOH 2% In-use 174 388 739 936 463 543475 std. dev. 18 20 38 122 53 102 40 10 min. soak 39 38 39 41 42 40 38std. dev. 1 2 3 1 3 3 3 30 min. soak 41 41 36 44 43 41 40 std. dev. 3 32 3 4 3 3 3% In-use 300 921 1009 1266 722 1082 1000 std. dev. 10 22 7764 102 3 50 10 min. soak 39 43 47 41 45 41 45 std. dev. 7 7 4 4 1 2 1 30min. soak 44 42 45 40 45 41 43 std. dev. 1 1 3 2 5 3 2 4% In-use 373 8621399 1294 845 1438 1283 std. dev. 5 56 79 192 100 94 70 10 min. soak 4242 44 47 45 43 39 std. dev. 3 4 3 3 5 1 5 30 min. soak 44 44 43 45 44 4546 std. dev. 2 3 1 3 2 1 7 5% In-use 442 1073 1569 1296 965 1561 1341std. dev. 12 31 78 166 13 62 37 10 min. soak 39 45 40 40 44 39 42 std.dev. 4 0 6 6 3 4 5 30 min. soak 37 45 35 46 42 41 40 std. dev. 3 5 7 4 13 5

As shown in Table 4, the triggerable binder formulation add-on levels,insolubilizing agent, and the composition of the wetting composition maybe chosen to provide a targeted in-use tensile strength or disposalstrength. The disposal strength of the treated fibrous substrate samplesreturns to the level of the residual wet strength of the fibroussubstrate sample during soaks in the hard water within 10 minutes orless.

EXAMPLE 4

The TBAL fibrous substrate sample from Example 1 was used to evaluatethe Baystrength® 85 polymer as a triggerable binder formulation. TheBaystrength® 85 polymer was applied to the fibrous substrate samples asdescribed above. The triggerable binder formulation add-on level foreach fibrous substrate was 5 wt %. The in-use tensile strength anddisposal strength for the treated fibrous substrate samples wereevaluated as described in Example 1. The treated fibrous substratesamples were allowed to equilibrate for in-use tensile strengthmeasurements, as described above, in wetting compositions of neatinsolubilizing agents as provided in Table 5 below. The use of neatinsolubilizing agents allowed for the examination of the relationship ofthe Solubility Parameter theory to the in-use tensile strength of thefibrous substrate samples. Methanol (MeOH), ethanol (EtOH), n-propanol(NPA), isopropanol (IPA), n-butanol (NBA), tert-butanol (TBA), acetone(ACE), and propylene glycol (PPG) were utilized as insolubilizingagents. The Baystrength® 85 polymer has a δ value of about 21(cal/cm³)^(1/2). According to Solubility Parameter theory, solventshaving similar δ values to that of an acceptable solvent would beacceptable as solvents as well. In addition, solvents having dissimilarδ values to an acceptable solvent would not be an acceptable solvent.Water, having a δ of 23.4 (cal/cm³)^(1/2), is known to be an excellentsolvent for polyacrylamide polymer, leading to good dispersibility offibrous substrates of the present invention treated with such atriggerable binder formulation. In accordance with the theory, one mightpredict that solvent having a δ value with the largest difference fromthe δ value of water would yield the highest in-use tensile strength. Ingeneral, such a trend is seen, within experimental error, for the groupsof solvents investigated as insolubilizing agents, with the exception ofthe tertiary alcohol, TBA. Note that CDWT of the TBAL fibrous substratesamples not treated with the triggerable binder formulation in selectedsolubilizing agents show only in-use tensile strength values thatreflect residual strength levels of the fibrous substrate samples. TABLE5 In-use tensile strength of TBAL fibrous substrates is variousinsolubilizing agents for the Baystrength ® 85 polymer as a triggerablebinder formulation. Solvent (cal/cm3){circumflex over ( )}0.5 CDWT(g/in.) Std.Dev. MeOH 14.5 455 21 EtOH 12.7 618 34 PPG 12.6 762 47 NPA11.9 737 74 IPA 11.5 768 51 NBA 11.4 851 24 TBA 10.6 646 25 ACE 9.9 83875 Dry TBAL 5% Binder 758 25 MeOH TBAL no binder 22 2 IPA TBAL no binder37 3 ACE TBAL no binder 32 2 Dry TBAL no binder 36 8

EXAMPLE 5

An anionic polyacrylamide polymer, commercially available under thetrade designation of Hercobond® 2000 polymer from Hercules Incorporatedlocated in Wilmington, Del., was evaluated as a triggerable binderformulation. The Hercobond® 2000 polymer had a weight-average molecularweight (M_(w)) of about 400,000 g/mole. The performance of theHercobond® 2000 polymer as a triggerable binder formulation was comparedwith Baystrength® 85 polymer on 6041 towel fibrous substrate samplescommercially available from the Kimberly-Clark Corporation. The 6041towel fibrous substrate samples have a basis weight of about 30 gsm anda caliper of about 0.5 mm. The 6041 towel fibrous substrate samples havea residual wet strength of about 60 gsm in water. The results presentedin Table 6 were not corrected for residual wet strength of the 6041towel fibrous substrate samples of this example. The Hercobond® 2000polymer and the Baystrength® 85 polymer were applied to the 6041 towelfibrous substrate samples as described above. The triggerable binderformulation add-on levels for each 6041 towel fibrous substrate sampleof the Hercobond® 2000 polymer range from 2.1 wt % to 4.1 wt % and ofthe Baystrength® 85 polymer range from 1.9 wt % to 4.0 wt %. The in-usetensile strength and disposal strength for the treated 6041 towelfibrous substrate samples were evaluated as described in Example 1, withone exception. Due to the sheet size of the 6041 towel fibrous substratesamples and the configuration of the handsheet spray unit, the treated6041 towel fibrous substrate samples were evaluated in Machine directionof the fibrous substrate. The treated 6041 towel fibrous substratesamples were allowed to equilibrate for in-use tensile strengthmeasurements, as described above, in a wetting composition having an IPAcontent of 80%. The treated 6041 towel fibrous substrate samples weresoaked in the hard water for disposal strength measurements for 10minutes and 30 minutes. The in-use tensile strength and disposalstrength measurements of the treated 6041 towel fibrous substratesamples are presented in Table 6. TABLE 6 Performance of Hercobond ®2000 polymer and Baystrength ® 85 polymer on 6041 towel fibroussubstrates in 80% IPA wetting composition. In-use (80% IPA) MDWT MDWTstd. Code Binder % Add-on MDWT std. dev 10 min. soak std. dev 30 min.soak dev. KCP 6041 none —  329 13  60 13  62 15 8635-154A Baystrength 854.0 1450 80 — — — — 8635-154B Baystrength 85 2.8 1213 47 — — — —8635-154C Baystrength 85 1.9 1048 93 110  8 103  6 8635-155A Hercobond2000 4.1 1153 68 — — — — 8635-155B Hercobond 2000 3.1 1129 89 — — — —8635-155C Hercobond 2000 2.1 1056 86 125 12 113 15

As presented in Table 6, both the Hercobond® 2000 polymer and theBaystrength® 85 polymer show high in-use tensile strength (greater thanabout 1000 g/in.) of the 6041 towel fibrous substrate samples treatedwith a triggerable binder formulation add-on level as low as 2 wt %.However the disposal strength of the treated 6041 towel fibroussubstrate samples appears to higher—thus the dispersibility of thetreated 6041 towel fibrous substrate samples appear to be lower and/orslower. The 6041 towel fibrous substrate samples treated with about 2 wt% add-on level of one of the triggerable binder formulations retainedabout 100 g/in. Disposal strength measurements were taken of the treated6041 towel fibrous substrate samples after soaking for 30 minutes inhard water.

EXAMPLE 6

The performance of the Hercobond® 2000 polymer was compared with threeother polyacrylamide polymers commercially available under the tradedesignations of SPP-949, SPP-376, and SPP-377 from Scientific PolymerProducts, Incorporated located in Ontario, N.Y., as triggerable binderformulations on the UCTAD fibrous substrate samples as described inExample 1. The SPP-949 polymer is a nonionic polyacrylamide withmolecular weight of about 10,000 g/mole. The SPP-376 polymer is acarboxyl modified polyacrylamide (having a low carboxyl content) with amolecular weight of about 200,000 g/mole. The SPP-377 polymer is acarboxyl modified polyacrylamide (having a high carboxyl content) with amolecular weight of about 200,000 g/mole. The Hercobond® 2000 polymer,SPP-949 polymer, SPP-376 polymer, and SPP-377 polymer were applied tothe fibrous substrate samples as described above. The triggerable binderformulation add-on levels for each fibrous substrate sample of theHercobond® 2000 polymer, SPP-949 polymer, SPP-376 polymer, and SPP-377polymer were at 2.0 wt %, 8.2 wt %, 4.2 wt %, and 4.4 wt %,respectively. The in-use tensile strength and disposal strength for thefibrous substrate samples were evaluated as described in Example 1. Thetreated fibrous substrate samples were allowed to equilibrate for in-usetensile strength measurements, as described above, in wettingcomposition having an IPA content ranging from 80% to 100%. The treatedfibrous substrate samples were soaked in the hard water for disposalstrength measurements for 10 minutes. The in-use tensile strength anddisposal strength measurements of the treated fibrous substrate samplesare presented in Table 7.

As shown in Table 7, the SPP-949 polymer requires slightly highertriggerable binder formulation add-on level to achieve a higher in-usetensile strength. The In-use tensile strength of the fibrous substratesamples treated with the SPP-949 polymer drops significantly when wateris utilized in the wetting composition. The SPP-376 polymer and theSPP-377 polymer show good in-use tensile strength of the fibroussubstrate samples in the wetting compositions having IPA contents of100% and 80%. The in-use tensile strength of the fibrous substratesample treated with the SPP-377 polymer drops significantly when wateris utilized in the wetting composition. The fibrous substrate samplestreated with the Hercobond® 2000 polymer, SPP-949 polymer, SPP-376polymer, and SPP-377 polymer show good disposal strength. TABLE 7Comparison of Hercobond ® 2000 polymer with SPP-949 polymer, SPP-376polymer, and SPP-377 polymer on UCTAD fibrous substrates in 80% and 100%IPA wetting compositions. In-use std. MDWT std. Code Binder % Add-on %IPA MDWT dev. 10 min. soak dev. 8635-184A Hercobond 2000 2.0 100 974 4031 14  8635-184A Hercobond 2000 2.0 80 497 21 33 2 8635-185A SPP-949 8.2100 598 25 31 14  8635-185A SPP-949 8.2 80 113 9 — — 8635-186A SPP-3764.2 100 1079 132 18 7 8635-186A SPP-376 4.2 80 783 51 16 8 8635-187ASPP-377 4.4 100 1131 70 32 3 8635-187A SPP-377 4.4 80 406 11 12 1

As shown in Table 7, the molecular weight and triggerable binderformulation may be chosen to provide a targeted in-use tensile strengthor disposal strength.

EXAMPLE 7

Polyvinylamine/vinylformamide co-polymers, commercially available underthe trade designation of Catiofast® 8104 co-polymer, Catiofast® 8087co-polymer, and Catiofast® 8106 co-polymer from BASF located in HollySprings, N.C., were evaluated as triggerable binder formulations on theTBAL fibrous substrate samples as described in Example 1. The Catiofast®8104 co-polymer is a 10% hydrolyzed poly-N-vinylformamide. TheCatiofast® 8087 co-polymer is a 50% hydrolyzed poly-N-vinylformamide.The Catiofast® 8106 co-polymer s a 90% hydrolyzed poly-N-vinylformamide.The Catiofast® 8104 co-polymer, Catiofast® 8087 co-polymer, andCatiofast® 8106 co-polymer were applied to the fibrous substrate samplesas described above. The triggerable binder formulation add-on level of 5wt % for each fibrous substrate sample of the Catiofast® 8104co-polymer, Catiofast® 8087 co-polymer, and Catiofast® 8106 co-polymer.The in-use tensile strength and disposal strength for the treatedfibrous substrate samples were evaluated as described in Example 1. Thetreated fibrous substrate samples were allowed to equilibrate for in-usetensile strength measurements, as described above, in wettingcompositions having an ethanol content of 100%, having an acetonecontent of 100%, and IPA content ranging from 60% to 100% as shown inTable 8 and Table 9. The treated fibrous substrate samples were soakedin the hard water for disposal strength measurements for 60 minutes. Thein-use tensile strength and disposal strength measurements of thetreated fibrous substrate samples are presented in Table 8 and Table 9.TABLE 8 In-use tensile strength of TBAL fibrous substrates in variousinsolubilizing agents for Catiofast ® 8104 co-polymer, Catiofast ® 8087co-polymer, and Catiofast ® 8106 co-polymer. CDWT CDWT (g/in.) (g/in.) 1hour Std. Binder Solvent In-use Std. Dev. Hard Water Dev. Catiofast 8104EtOH 297 16 13 18 Catiofast 8104 IPA 431 17 28 10 Catiofast 8104 ACE 38949 20 13 Catiofast 8087 EtOH 230 15 68 10 Catiofast 8087 IPA 444 25 5510 Catiofast 8087 ACE 405 51 61 10 Catiofast 8106 EtOH 222 20 86 8Catiofast 8106 IPA 322 11 90 6 Catiofast 8106 ACE 261 49 80 19

As shown in Table 8, the in-use tensile strength and disposal strengthof the treated fibrous substrate samples is a function of triggerablebinder formulation type and insolubilizing agent type. Dispersibilityappears to be better for lower degrees of hydrolysis of the triggerablebinder formulation. TABLE 9 In-use tensile strength of TBAL fibroussubstrates for Catiofast ® 8104 co-polymer in wetting compositionshaving IPA content. CDWT (g/in.) % IPA In-use Std. Dev. 60 140 1 70 1448 80 194 27 90 328 13 100 431 17

As shown in Table 9, the in-use tensile strength of the fibroussubstrate samples treated with the Catiofast® 8104 co-polymer deceaseswith increasing water content of the wetting composition.

EXAMPLE 8

An un-bonded air-laid fibrous substrate was prepared using CF 405 woodpulp fibers, commercially available from Weyerhaeuser (completename/location) via a air-forming apparatus used in the art forair-laying processes. The fibrous substrate was deposited and sandwichedbetween two thin tissue carrier sheets to allow the fibrous substrate tobe rolled into a stable roll. The width of the fibrous substrate isabout 8 inches. The fibrous substrate has a basis weight of 58 gsm (±2)and caliper of 1.0 mm (±0.1). The Hercobond® 2000 polymer, as atriggerable binder formulation, was applied to the fibrous substrate asdescribed in Example 1, with the following exceptions: square fibroussubstrate samples having 8.25″×8.25″ dimensions are cut from the fibroussubstrate roll; the fibrous substrate samples are carefully separatedfrom the tissue carrier sheets and placed on a 10.25″×8.25″ nylonscreen; and, a rubber mask was placed over the fibrous substrate sampleexposing a 7.5″×7.5″ area. This assembly of the fibrous substratesample, nylon screen, and rubber mask is placed on the stationary sampleholder section of the handsheet spray unit. The triggerable binderformulation add-on level for the exposed first surface of each fibroussubstrate sample was 5 wt %. The rubber mask is removed and the fibroussubstrate sample, still retained on the nylon screen, is placed in theTAD and dried at 193° C. for 30 seconds. After drying, the fibroussubstrate sample is removed from the TAD. The fibrous substrate sampleis removed from the nylon screen and replaced onto the nylon screen withthe treated first surface in contact with the nylon screen. The rubbermask is placed on the second side of the fibrous substrate sample. Thetriggerable binder formulation add-on level for the exposed secondsurface of each fibrous substrate sample was 5 wt %. The rubber mask isremoved and the fibrous substrate sample, still retained on the nylonscreen, is placed in the TAD and dried at 193° C. for 30 seconds. Afterdrying, the fibrous substrate sample is removed from the TAD. The fibersfrom the un-bonded edges of the treated fibrous substrate are removed byhand. The treated fibrous substrate samples are trimmed on a laboratorycutter to provide a treated fibrous substrate sample having thedimensions of 6.5″ (MD)×5.5″ (CD). The total triggerable binderformulation add-on level for the treated fibrous substrate samples was10 wt %. The treated fibrous substrate sample has a basis weight of 65gsm and a caliper of 1.6 mm. The dry treated fibrous substrate samplesare cut into strips having the dimensions of 1″ by 4.5″. The strips ofthe treated fibrous substrate samples are allowed to equilibrate forin-use tensile strength measurements in a wetting composition having anIPA content of 80%. The MD and CD in-use tensile strengths of thetreated fibrous substrate samples were 912 g/in. (±58) and 746 g/in.(±68), respectively. The strips of the treated fibrous substrate samplesare transferred to 100 ppm hard water for a 10 minute soak. Disposalstrength measurements are taken after the soaking period. In both cases,the strips were too weak to accurately measure the tensile strength (>20g/in). In a further experiment, 6.5″×5.5″ prototypes were wet withapproximately 300-700% add-on level of 80% IPA. The prototype wet wipesgave excellent durability and adequate in-use properties to be used forhard surface cleaning and other applications. When the wipes were placedin a 2L beaker filled with tap water and gently stirred, they broke intosmall pieces and fibers in a few seconds.

EXAMPLE 9

The Baystrength® 711 polymer was evaluated as a triggerable binderformulation in a wet-laid handsheet fibrous substrate samples. Thewet-laid handsheet fibrous substrate samples were prepared by dispersing24 grams of oven-dried eucalyptus wood pulp fibers in approximately 2liters of water. The fiber slurry was prepared through an application of5 minutes of British Standard disintegration using equipmentcommercially available under the trade designation of Noram fromLorentzen and Wettre located in Pointe Claire, Quebec, and furtherdiluted with water to a total volume of approximately 8 liters. TheBaystrength® 711 polymer was added to the fiber slurry at a level of 0.3weight percent based upon final fibrous substrate composition. Thetreated wet-laid handsheet fibrous substrate samples were created in aforming mold, pressed for one minute at a pressure of 98 psi, and driedfor two minutes on a steam dryer at 105° C. using handsheet equipmentcommercially available from Voith Incorporated located in Appleton, Wis.The treated wet-laid handsheet fibrous substrate samples had a basisweight of 60 gsm. The treated fibrous substrate samples were allowed toequilibrate for in-use tensile strength measurements, as describedabove, in aqueous or neat alcohol wetting compositions having an IPAcontent of between 60 and 100 percent. The in-use tensile strength ofthe treated fibrous substrate samples are presented in Table 10. Thedisposal strength of the treated fibrous substrate samples afterexposure for 60 minutes soaks in 200 ppm hard water are also shown inTable 10. The wet strength decay was calculated for each of the treatedfibrous substrate samples by dividing the difference of the in-usetensile strength and the disposal strength by the in-use tensilestrength for a given treated fibrous substrate sample. The wet strengthdecay values are presented in Table 10.

EXAMPLE 10

The Baystrength® 711 polymer was evaluated as a triggerable binderformulation in a wet-laid handsheet fibrous substrate samples. Thewet-laid handsheet fibrous substrate samples were prepared by dispersing24 grams of oven-dried eucalyptus wood pulp fibers in approximately 2liters of water. The fiber slurry was prepared through an application of5 minutes of British Standard disintegration using the Noram equipmentand further diluted with water to a total volume of approximately 8liters. The Baystrength® 711 polymer was added to the fiber slurry at alevel of 0.6 weight percent based upon final fibrous substratecomposition. The treated wet-laid handsheet fibrous substrate sampleswere created in a forming mold, pressed for one minute at a pressure of98 psi, and dried for two minutes on a steam dryer at 105° C. usinghandsheet equipment commercially available from Voith Incorporatedlocated in Appleton, Wis. The treated wet-laid handsheet fibroussubstrate samples had a basis weight of 60 gsm. The treated fibroussubstrate samples were allowed to equilibrate for in-use tensilestrength measurements, as described above, in aqueous or neat alcoholwetting compositions having an IPA content of between 60 and 100percent. The in-use tensile strength of the treated fibrous substratesamples are presented in Table 10. The disposal strength of the treatedfibrous substrate samples after exposure for 60 minutes soaks in 200 ppmhard water are also shown in Table 10. The wet strength decay wascalculated for each of the treated fibrous substrate samples by dividingthe difference of the in-use tensile strength and the disposal strengthby the in-use tensile strength for a given treated fibrous substratesample. The wet strength decay values are presented in Table 10.

EXAMPLE 11

The Baystrength® 711 polymer was evaluated as a triggerable binderformulation in a wet-laid handsheet fibrous substrate samples. Thewet-laid handsheet fibrous substrate samples were prepared by dispersing24 grams of oven-dried eucalyptus wood pulp fibers in approximately 2liters of water. The fiber slurry was prepared through an application of5 minutes of British Standard disintegration using the Noram equipment,and further diluted with water to a total volume of approximately 8liters. The Baystrength® 711 polymer was added to the fiber slurry at alevel of 1.0 weight percent based upon final fibrous substratecomposition. The treated wet-laid handsheet fibrous substrate sampleswere created in a forming mold, pressed for one minute at a pressure of98 psi, and dried for two minutes on a steam dryer at 105° C. usinghandsheet equipment commercially available from Voith Incorporatedlocated in Appleton, Wis. The treated wet-laid handsheet fibroussubstrate samples had a basis weight of 60 gsm. The treated fibroussubstrate samples were allowed to equilibrate for in-use tensilestrength measurements, as described above, in aqueous or neat alcoholwetting compositions having an IPA content of between 60 and 100percent. The in-use tensile strength of the treated fibrous substratesamples are presented in Table 10. The disposal strength of the treatedfibrous substrate samples after exposure for 60 minutes soaks in 200 ppmhard water are also shown in Table 10. The wet strength decay wascalculated for each of the treated fibrous substrate samples by dividingthe difference of the in-use tensile strength and the disposal strengthby the in-use tensile strength for a given treated fibrous substratesample. The wet strength decay values are presented in Table 10. TABLE10 Fibrous substrate performance for Baystrength ® 711 polymerconcentration and IPA concentration in wetting compositions.Baystrength ® 711 In-use Tensile Disposal Wet Strength Dosage IPAStrength Strength Decay (%) (%) (g/in.) (g/in.) (%) 0.3 60 147 ± 33 39 ±1 73 0.6 60 260 ± 9  68 ± 9 74 1.0 60 362 ± 11  95 ± 13 74 0.3 80 364 ±11  42 ± 12 88 0.6 80 500 ± 17 82 ± 2 84 1.0 80 731 ± 18 123 ± 6  83 0.3100 1277 ± 32  43 ± 2 97 0.6 100 1665 ± 108  65 ± 10 96 1.0 100 1964 ±128 97 ± 9 95

As shown in Table 10, the in-use strength and the disposal strength ofthe treated fibrous substrate samples are a function of concentrationsof the triggerable binder formulation and insolubilizing agent.

EXAMPLE 12

The Baystrength® 711 polymer was evaluated as a triggerable binderformulation in a wet-laid handsheet fibrous substrate samples. Thewet-laid handsheet fibrous substrate samples were prepared by dispersing24 grams of oven-dried LL-19 wood pulp fibers in approximately 2 litersof water. The fiber slurry was prepared through an application of 5minutes of British Standard disintegration using the Noram equipment andfurther diluted with water to a total volume of approximately 8 liters.The Baystrength® 711 polymer was added to the fiber slurry at a level of0.3 weight percent based upon final fibrous substrate composition. Thetreated wet-laid handsheet fibrous substrate samples were created in aforming mold, pressed for one minute at a pressure of 98 psi, and driedfor two minutes on a steam dryer at 105° C. using handsheet equipmentcommercially available from Voith Incorporated located in Appleton, Wis.The treated wet-laid handsheet fibrous substrate samples had a basisweight of 60 gsm. The treated fibrous substrate samples were allowed toequilibrate for in-use tensile strength measurements, as describedabove, in aqueous alcohol wetting compositions having an IPA content ofbetween 80 and 90 percent. The in-use tensile strength of the treatedfibrous substrate samples are presented in Table 11. The disposalstrength of the treated fibrous substrate samples after exposure for 60minutes soaks in 200 ppm hard water are also shown in Table 11. The wetstrength decay was calculated for each of the treated fibrous substratesamples by dividing the difference of the in-use tensile strength andthe disposal strength by the in-use tensile strength for a given treatedfibrous substrate sample. The wet strength decay values are presented inTable 11. TABLE 11 Effect of wood pulp fiber type upon in-use tensilestrength and disposal strength performance of fibrous substrates forBaystrength ® 711 polymer. In-use Tensile Disposal Wet Strength IPAStrength Strength Decay Wood Fiber (%) (g/in.) (g/in.) (%) Eucalyptus 80731 ± 18 123 ± 6  83 LL-19 80 828 ± 45  80 ± 10 90 Eucalyptus 85 1006 ±26  27 ± 6 97 LL-19 85 1238 ± 31  106 ± 14 91 Eucalyptus 90 1359 ± 11618 ± 5 99 LL-19 90 1505 ± 149 122 ± 2  92

As shown in Table 11, the in-use tensile strength and the disposalstrength are a function of the wood pulp fiber type.

EXAMPLE 13

The performance of Baystrength® 711 (Example 11) was compared withCatiofast® 8104 polymer and a crosslinking, cationic polyacrylamidepolymer, commercially available under the trade designation of Parez®631 polymer from Cytec Industries located in West Paterson, N.J., astriggerable binder formulations in wet-laid handsheet fibrous substratesamples. The wet-laid handsheet fibrous substrate samples were preparedby dispersing 24 grams of oven-dried eucalyptus wood pulp fibers inapproximately 2 liters of water. The fiber slurry was prepared throughan application of 5 minutes of British Standard disintegration using theNoram equipment, and further diluted with water to a total volume ofapproximately 8 liters. The Parez® 631 or Catiofast® 8104 polymers wereadded to the fiber slurry at a level of 1.0 weight percent based uponfinal fibrous substrate composition. The treated wet-laid handsheetfibrous substrate samples were created in a forming mold, pressed forone minute at a pressure of 98 psi, and dried for two minutes on a steamdryer at 105° C. using handsheet equipment commercially available fromVoith Incorporated located in Appleton, Wis. The treated wet-laidhandsheet fibrous substrate samples had a basis weight of 60 gsm. Thetreated fibrous substrate samples were allowed to equilibrate for in-usetensile strength measurements, as described above, in aqueous or neatalcohol wetting compositions having an IPA content of between 60 and 100percent. The in-use tensile strength of the treated fibrous substratesamples are presented in Table 12. The disposal strength of the treatedfibrous substrate samples after exposure for 60 minutes soaks in 200 ppmhard water are also shown in Table 12. The wet strength decay wascalculated for each of the treated fibrous substrate samples by dividingthe difference of the in-use tensile strength and the disposal strengthby the in-use tensile strength for a given treated fibrous substratesample. The wet strength decay values are presented in Table 12. TABLE12 Comparison of Baystrength ® 711 polymer with Parez ® 631 polymer andCatiofast ® 8104 polymer on wet-laid handsheet fibrous substrates in 60%to 100% IPA wetting compositions. In-use Tensile Disposal Wet StrengthIPA Strength Strength Decay Polymer (%) (g/in.) (g/in.) (%) Parez ® 63160 379 ± 9  244 ± 91 36 Baystrength ® 711 60 362 ± 11  95 ± 13 74Catiofast ® 8104 60 165 ± 18 0 100 Parez ® 631 80  794 ± 154 194 ± 45 76Baystrength ® 711 80 731 ± 18 123 ± 6  83 Catiofast ® 8104 80 367 ± 14 0100 Parez ® 631 100 2562 ± 103 174 ± 42 93 Baystrength ® 711 100 1964 ±128 97 ± 9 95 Catiofast ® 8104 100 1301 ± 99  0 100

As shown in Table 12, the in-use tensile strength and the disposalstrength are a function of the triggerable binder formulation type andof the concentrations of the triggerable binder formulation and theinsolubilizing agent.

EXAMPLE 14

The performance of the Baystrength® 711 polymer was evaluated as atriggerable binder formulation on wet-laid, 40 gsm handsheet fibroussubstrate samples. One set of wet-laid handsheet fibrous substratesamples were prepared by dispersing 16 grams of oven-dried eucalyptuswood pulp fibers in approximately 2 liters of water. The fiber slurrywas prepared through an application of 5 minutes of British Standarddisintegration using the Noram equipment, and further diluted with waterto a total volume of approximately 8 liters. The Baystrength® 711polymer was added to the fiber slurry at a level of 2.0 weight percentbased upon final fibrous substrate composition. The treated wet-laidhandsheet fibrous substrate samples were created in a forming mold,pressed for one minute at a pressure of 98 psi, and dried for twominutes on a steam dryer at 105° C. using handsheet equipmentcommercially available from Voith Incorporated located in Appleton, Wis.

Another set of wet-laid handsheet fibrous substrate samples wereprepared by dispersing 16 grams of oven-dried LL-19 wood pulp fibers inapproximately 2 liters of water. The fiber slurry was prepared throughan application of 5 minutes of British Standard disintegration using theNoram equipment, and further diluted with water to a total volume ofapproximately 8 liters. The Baystrength® 711 polymer was added to thefiber slurry at a level of 2.0 weight percent based upon final fibroussubstrate composition. The treated wet-laid handsheet fibrous substratesamples were created in a forming mold, pressed for one minute at apressure of 98 psi, and dried for two minutes on a steam dryer at 105°C. using handsheet equipment commercially available from VoithIncorporated located in Appleton, Wis.

Both sets of treated fibrous substrate samples were allowed toequilibrate for in-use tensile strength measurements, as describedabove, in aqueous or neat alcohol wetting compositions having an IPAcontent of between 80 and 100 percent. The in-use tensile strength ofthe treated fibrous substrate samples are presented in Table 13. Thedisposal strength of the treated fibrous substrate samples afterexposure for 60 minutes soaks in 200 ppm hard water are also shown inTable 13. The wet strength decay was calculated for each of the treatedfibrous substrate samples by dividing the difference of the in-usetensile strength and the disposal strength by the in-use tensilestrength for a given treated fibrous substrate sample. The wet strengthdecay values are presented in Table 13. TABLE 13 Effect of wood pulpfiber type upon in-use tensile strength and disposal strengthperformance of fibrous substrates for Baystrength ® 711 polymer. In-useTensile Disposal Wet Strength IPA Strength Strength Decay Wood Fiber (%)(g/in.) (g/in.) (%) Eucalyptus 80 615 ± 40 0 100 LL-19 80 775 ± 66 93 ±11 88 Eucalyptus 85  806 ± 114 0 100 LL-19 85  928 ± 125 80 ± 5  91Eucalyptus 90 1054 ± 151 0 100 LL-19 90 1231 ± 121 68 ± 20 94 Eucalyptus95 1476 ± 111 0 100 LL-19 95 1699 ± 143 75 ± 9  96 Eucalyptus 100 1711 ±366 0 100 LL-19 100 2398 ± 251 45 ± 13 98

As shown in Table 13, the in-use tensile strength and the disposalstrength are a function of wood pulp fiber type.

It will be appreciated that details of the foregoing embodiments, givenfor purposes of illustration, are not to be construed as limiting thescope of this invention. Although only a few exemplary embodiments ofthis invention have been described in detail above, those skilled in theart will readily appreciate that many modifications are possible in theexemplary embodiments without materially departing from the novelteachings and advantages of this invention. Accordingly, all suchmodifications are intended to be included within the scope of thisinvention, which is defined in the following claims and all equivalentsthereto. Further, it is recognized that many embodiments may beconceived that do not achieve all of the advantages of some embodiments,particularly of the preferred embodiments, yet the absence of aparticular advantage shall not be construed to necessarily mean thatsuch an embodiment is outside the scope of the present invention.

1. A wet wipe product comprising: a fibrous substrate comprising fibers;and, a triggerable binder formulation for binding the fibers in thefibrous substrate wherein the triggerable binder formulation is selectedfrom the group comprising acrylamide polymers and polymer formulations,vinylamide/amine polymers and polymer formulations, and mixturesthereof, wherein the triggerable binder formulation is insoluble in awetting composition comprising an insolubilizing agent and thetriggerable binder formulation is dispersible in disposal water.
 2. Thewet wipe product of claim 1, wherein the wet wipe product is wetted bythe wetting composition.
 3. The wet wipe product of claim 2, wherein thewetting composition has an insolubilizing agent content of at leastabout 50%.
 4. The wet wipe product of claim 1, wherein the disposalwater comprises less than about 50% of the insolubilizing agent.
 5. Thewet wipe product of claim 1, wherein the fibrous substrate has atriggerable binder formulation add-on level of about 0.5 wt % to about25 wt %.
 6. The wet wipe product of claim 1, wherein the insolubilizingagent is selected from the group comprising a lower level alcohol, alower level glycol, a lower level ketone, and mixtures thereof.
 7. Thewet wipe product of claim 1, wherein the insolubilizing agent isselected from the group comprising methyl alcohol, ethyl alcohol,n-propyl alcohol, isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol,tert-butyl alcohol, ethylene glycol, 1,2 propandiol (propylene glycol),1,3 propane diol, acetone, methylethyl ketone, and mixtures thereof. 8.The wet wipe product of claim 1, wherein the triggerable binderformulation is a polymerization product comprising acrylamide orvinylamide/amine monomers and, optionally, at least one monomer selectedfrom the group comprising acrylic acid, methacrylic acid and theirsalts, 2-acrylamido-2-methyl-1 propanesulfonic acid and its salts, vinylsulfonic acid and their salts, other sulfonate monomers such aspotassium (3-sulfopropyl) acrylate, sodium styrene sulfonate, andphosphonate/phosphonic acids.
 9. The wet wipe product of claim 1,wherein the triggerable binder formulation is a polymerization productcomprising acrylamide or vinylamide/amine monomers and, optionally, atleast one monomer selected from the group comprising N-isopropylacrylamide and other acrylamide derivatives, 2-hydroxylethylmethacrylate, vinyl pyrrolidone, methylvinyl ether, polyethylene glycolacrylates, and polyethylene glycol methacrylates.
 10. The wet wipeproduct of claim 1, wherein the triggerable binder formulation is apolymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising N,N-dimethyl-N-(2-methacryloyloxyethyl)-N-(3-sulfopropyl)ammonium betaine,N,N-dimethyl-N-(2-methacrylamidopropyl)-N-(3-sulfopropyl) ammoniumbetaine, 1-(3-Sulfopropyl)-2-vinylpyridinium betaine,N-(3-carboxypropyl)-N-methacrylamido-ethyl-N,N-dimethyl ammoniumbetaine, and 4-vinylpiperidinium ethanecarboxy betaine.
 11. The wet wipeproduct of claim 1, wherein the triggerable binder formulation is apolymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising [2-(acryloxy)ethyl] trimethyl ammonium chloride,[2-(methacryloxy)ethyl]trimethyl ammonium chloride, (3-acrylamidopropyl)trimethyl ammonium chloride, N,N-diallyldimethyl ammonium chloride,[2-(acryloxy)ethyl] dimethylbenzyl ammonium chloride,[2-(methacryloxy)ethyl] dimethylbenzyl ammonium chloride,[2-(acryloxy)ethyl] dimethyl ammonium chloride, and[2-(methacryloxy)ethyl) dimethyl ammonium chloride.
 12. The wet wipeproduct of claim 1, wherein the triggerable binder formulation is apolymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising vinylpyridine, dimethylaminoethyl acrylate, anddimethylaminoethyl methacrylate.
 13. The wet wipe product of claim 1,wherein the triggerable binder formulation is a polymerization productcomprising acrylamide or vinylamide/amine monomers and, optionally, atleast one monomer selected from the group comprising methyl acrylate,ethyl acrylate, butyl acrylate, substituted acrylamide, and alkyl vinylether.
 14. The wet wipe product of claim 1, wherein the triggerablebinder formulation is a polymerization product comprising acrylamide orvinylamide/amine monomers and, optionally, at least one monomer selectedfrom the group comprising N-vinylformamide, N-vinyl alkylamides,polyvinylpyrrolidone, and polyvinylcaprolactam.
 15. The wet wipe productof claim 1, wherein the wet wipe product has an in-use tensile strengthof about 300 g/in or greater.
 16. The wet wipe product of claim 1,wherein the wet wipe product has a disposal strength of about 75 g/in.or less.
 17. The wet wipe product of claim 1, wherein the fibroussubstrate is air-laid, wet-laid, or coform.
 18. A wet wipe productcomprising: a fibrous substrate comprising fibers; a triggerable binderformulation composition for binding the fibers in the fibrous substratewherein the triggerable binder formulation is selected from the groupcomprising acrylamide polymers and polymer formulations,vinylamide/amine polymers and polymer formulations, and mixturesthereof; and, a wetting composition comprising an insolubilizing agentselected from the group comprising a lower level alcohol, a lower levelglycol, a lower level ketone, and mixtures thereof, wherein thetriggerable binder formulation is insoluble in the wetting compositionand the triggerable binder formulation is dispersible in disposal water.19. The wet wipe product of claim 18, wherein the wetting compositionhas an insolubilizing agent content of at least about 50%.
 20. The wetwipe product of claim 18, wherein the disposal water comprises less thanabout 50% of the insolubilizing agent.
 21. The wet wipe product of claim18, wherein the fibrous substrate has a triggerable binder formulationadd-on level of about 0.5 wt % to about 25 wt %.
 22. The wet wipeproduct of claim 18, wherein the insolubilizing agent is selected fromthe group comprising methyl alcohol, ethyl alcohol, n-propyl alcohol,isopropyl alcohol, n-butyl alcohol, sec-butyl alcohol, tert-butylalcohol, ethylene glycol, 1,2 propandiol (propylene glycol), 1,3 propanediol, acetone, methylethyl ketone, and mixtures thereof.
 23. The wetwipe product of claim 18, wherein the triggerable binder formulation isa polymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising acrylic acid, methacrylic acid and their salts,2-acrylamido-2-methyl-1 propanesulfonic acid and its salts, vinylsulfonic acid and their salts, other sulfonate monomers such aspotassium (3-sulfopropyl) acrylate, sodium styrene sulfonate, andphosphonate/phosphonic acids.
 24. The wet wipe product of claim 18,wherein the triggerable binder formulation is a polymerization productcomprising acrylamide or vinylamide/amine monomers and, optionally, atleast one monomer selected from the group comprising N-isopropylacrylamide and other acrylamide derivatives, 2-hydroxylethylmethacrylate, vinyl pyrrolidone, methylvinyl ether, polyethylene glycolacrylate, and polyethylene glycol methacrylates.
 25. The wet wipeproduct of claim 18, wherein the triggerable binder formulation is apolymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising N,N-imethyl-N-(2-methacryloyloxyethyl)-N-(3-sulfopropyl)ammonium betaine,N,N-dimethyl-N-(2-methacrylamidopropyl)-N-(3-sulfopropyl) ammoniumbetaine, 1-(3-Sulfopropyl)-2-vinylpyridinium betaine,N-(3-carboxypropyl)-N-methacrylamido-ethyl-N,N-dimethyl ammoniumbetaine, and 4-vinylpiperidinium ethanecarboxy betaine.
 26. The wet wipeproduct of claim 18, wherein the triggerable binder formulation is apolymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising [2-(acryloxy)ethyl] trimethyl ammonium chloride,[2-(methacryloxy)ethyl] trimethyl ammonium chloride,(3-acrylamidopropyl) trimethyl ammonium chloride, N,N-diallyldimethylammonium chloride, [2-(acryloxy)ethyl] dimethylbenzyl ammonium chloride,[2-(methacryloxy)ethyl] dimethylbenzyl ammonium chloride,[2-(acryloxy)ethyl] dimethyl ammonium chloride, and(2-(methacryloxy)ethyl] dimethyl ammonium chloride.
 27. The wet wipeproduct of claim 18, wherein the triggerable binder formulation is apolymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising vinylpyridine, dimethylaminoethyl acrylate, anddimethylaminoethyl methacrylate.
 28. The wet wipe product of claim 18,wherein the triggerable binder formulation is a polymerization productcomprising acrylamide or vinylamide/amine monomers and, optionally, atleast one monomer selected from the group comprising methyl acrylate,ethyl acrylate, butyl acrylate, substituted acrylamide, and alkyl vinylether.
 29. The wet wipe product of claim 18, wherein the triggerablebinder formulation is a polymerization product comprising acrylamide orvinylamide/amine monomers and, optionally, at least one monomer selectedfrom the group comprising N-vinylformamide, N-vinyl alkylamides,polyvinylpyrrolidone, and polyvinylcaprolactam.
 30. The wet wipe productof claim 18, wherein the wet wipe product has an in-use tensile strengthof about 300 g/in or greater.
 31. The wet wipe product of claim 18,wherein the wet wipe product has a disposal strength of about 75 g/in.or less.
 32. The wet wipe product of claim 18, wherein the fibroussubstrate is air-laid, wet-laid, or coform.
 33. A method of making a wetwipe product comprising: providing a triggerable binder formulationwherein the triggerable binder formulation selected from the groupcomprising acrylamide polymers and polymer formulations,vinylamide/amine polymers and polymer formulations, and mixturesthereof; and, providing a fibrous substrate comprising fibers, whereinthe triggerable binder formulation is insoluble in a wetting compositioncomprising an insolubilizing agent and the triggerable binderformulation is dispersible in disposal water.
 34. The method of claim33, wherein the wetting composition has an insolubilizing agent contentof at least about 50%.
 35. The method of claim 33, wherein the disposalwater comprises less than about 50% of the insolubilizing agent.
 36. Themethod of claim 33, wherein the fibrous substrate has a triggerablebinder formulation add-on level of about 0.5 wt % to about 25 wt %. 37.The method of claim 33, wherein the insolubilizing agent is selectedfrom the group comprising a lower level alcohol, a lower level glycol, alower level ketone, and mixtures thereof.
 38. The method of claim 33,wherein the insolubilizing agent is selected from the group comprisingmethyl alcohol, ethyl alcohol, n-propyl alcohol, isopropyl alcohol,n-butyl alcohol, sec-butyl alcohol, tert-butyl alcohol, ethylene glycol,1,2 propandiol (propylene glycol), 1,3 propane diol, acetone,methylethyl ketone, and mixtures thereof.
 39. The method of claim 33,wherein the triggerable binder formulation is a polymerization productcomprising acrylamide or vinylamide/amine monomers and, optionally, atleast one monomer selected from the group comprising acrylic acid,methacrylic acid and their salts, 2-acrylamido-2-methyl-1propanesulfonic acid and its salts, vinyl sulfonic acid and their salts,other sulfonate monomers such as potassium (3-sulfopropyl) acrylate,sodium styrene sulfonate, and phosphonate/phosphonic acids.
 40. Themethod of claim 33, wherein the triggerable binder formulation is apolymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising N-isopropyl acrylamide and other acrylamide derivatives,2-hydroxylethyl methacrylate, vinyl pyrrolidone, methylvinyl ether,polyethylene glycol acrylate, and polyethylene glycol methacrylates. 41.The method of claim 33, wherein the triggerable binder formulation is apolymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising N,N-dimethyl-N-(2-methacryloyloxyethyl)-N-(3-sulfopropyl)ammonium betaine,N,N-dimethyl-N-(2-methacrylamidopropyl)-N-(3-sulfopropyl) ammoniumbetaine, 1-(3-Sulfopropyl)-2-vinylpyridinium betaine,N-(3-carboxypropyl)-N-methacrylamido-ethyl-N,N-dimethyl ammoniumbetaine, and 4-vinylpiperidinium ethanecarboxy betaine.
 42. The methodof claim 33, wherein the triggerable binder formulation is apolymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising [2-(acryloxy)ethyl] trimethyl ammonium chloride,[2-(methacryloxy)ethyl] trimethyl ammonium chloride,(3-acrylamidopropyl) trimethyl ammonium chloride, N,N-diallyldimethylammonium chloride, [2-(acryloxy)ethyl] dimethylbenzyl ammonium chloride,[2-(methacryloxy)ethyl] dimethylbenzyl ammonium chloride,[2-(acryloxy)ethyl] dimethyl ammonium chloride, and[2-(methacryloxy)ethyl] dimethyl ammonium chloride.
 43. The method ofclaim 33, wherein the triggerable binder formulation is a polymerizationproduct comprising acrylamide or vinylamide/amine monomers and,optionally, at least one monomer selected from the group comprisingvinylpyridine, dimethylaminoethyl acrylate, and dimethylaminoethylmethacrylate.
 44. The method of claim 33, wherein the triggerable binderformulation is a polymerization product comprising acrylamide orvinylamide/amine monomers and, optionally, at least one monomer selectedfrom the group comprising methyl acrylate, ethyl acrylate, butylacrylate, substituted acrylamide, and alkyl vinyl ether.
 45. The methodof claim 33, wherein the triggerable binder formulation is apolymerization product comprising acrylamide or vinylamide/aminemonomers and, optionally, at least one monomer selected from the groupcomprising N-vinylformamide, N-vinyl alkylamides, polyvinylpyrrolidone,and polyvinylcaprolactam.
 46. The method of claim 33, wherein the wetwipe product has an in-use tensile strength of about 300 g/in orgreater.
 47. The method of claim 33, wherein the wet wipe product has adisposal strength of about 75 g/in. or less.
 48. The method of claim 33,wherein the fibrous substrate is air-laid, wet-laid, or coform.
 49. Themethod of claim 33, further comprising treating the fibrous substratewith the triggerable binder formulation.
 50. The method of claim 33,wherein the fibers of the fibrous substrate are treated with thetriggerable binder formulation prior to the formation of the fibroussubstrate.